The Future is Forming by Engineering Quality Solutions www.EQSgroup.com

Nissan to Use 1.2GPa Steel to Reduce Vehicle Weight

noreply@blogger.com (Engineering Quality Solutions) — Wed, 13 Mar 2013 21:25:00 +0000

Nissan just announced the expanded use of an Advanced High Strength Steel (AHSS) that has a tensile strength of 1.2GPa (= 1,200MPa = 175 ksi = 175,000 psi). This follows their initial announcement in October 2011.

Things we've learned:

The complex microstructure consists of 2 hard phases and 1 soft phase.
The scale of the microstructure is micron / submicron.
A new welding process needed to be developed to accommodate the microstructure.
This new grade of steel was developed jointly by Nippon Steel, Kobe Steel, and Nissan. (Nippon recently merged with Sumitomo Steel to form Nippon Steel & Sumitomo Metal Corporation)
Nissan plans to use AHSS on up to 25% of all body parts.

This is a great technical achievement, but a bigger hurdle may have been in the collaborative alloy development approach: two steel competitors partnered with one of their customers.

How will this play out? Will the steel companies be allowed to supply the grade to other automakers? Will the steel companies be allowed to market the grade through their partners? Nippon has Joint Ventures with ArcelorMittal in the USA and Ternium in Mexico; Kobe has Joint Ventures with US Steel.

http://www.nissan-global.com/EN/NEWS/2013/_STORY/130312-01-e.html

Danny Schaeffler
Engineering Quality Solutions, Inc. ... http://www.EQSgroup.com
4M Partners, LLC ... http://www.Learning4M.com

Acura RLX will have Multi-Metal Doors: Aluminum Skins and Steel Inners

noreply@blogger.com (Engineering Quality Solutions) — Thu, 28 Feb 2013 13:54:00 +0000

Honda has developed a production manufacturing process that lets them join steel to aluminum skin panels. The first application of this will be on the 2014 Acura RLX, which will have an aluminum door skin joined to a steel door inner. This technique is projected to reduce the weight of the doors by 17%, and improve ride stability by concentrating the weight closer to the vehicle center. This application is a result of three key breakthroughs: development of a 3D Lock Seam structure where the aluminum outer is hemmed twice, development of a process so the adhesive completely fills the gap between the panels, and development of a technique to account for the different thermal characteristics between steel and aluminum.

http://world.honda.com/news/2013/4130218New-Technology-Join-Steel-Aluminum/index.html

Danny Schaeffler
Engineering Quality Solutions, Inc. ... http://www.EQSgroup.com
4M Partners, LLC ... http://www.Learning4M.com

Supplies and Suppliers Limited Chrysler Sales in 2012

noreply@blogger.com (Engineering Quality Solutions) — Tue, 26 Feb 2013 14:37:00 +0000

Sales of the 2013 Dodge Dart were lower than initially projected in 2012 because only manual transmissions were available at launch, with a six-speed automatic sourced from Hyundai serving as a stopgap until a promised nine-speed automatic is available. In addition, Chrysler reportedly is pressuring Jeep Wrangler and Grand Cherokee suppliers to increase capacity after bottlenecks cost the company 60,000 to 70,000 lost sales globally in 2012.

http://www.autonews.com/apps/pbcs.dll/article?AID=/20130114/RETAIL01/130119913/marchionne-says-darts-slow-start-due-to-transmission-availability

http://www.autonews.com/apps/pbcs.dll/article?AID=/20130114/OEM02/130119892/chrysler-lost-60-70k-jeep-sales-to-production-bottlenecks-marchionne

Danny Schaeffler
Engineering Quality Solutions, Inc. ... http://www.EQSgroup.com
4M Partners, LLC ... http://www.Learning4M.com

Hardness Testing: Rockwell / Brinell / Vickers Scales and Applicability to Stamped Sheet Steel Parts

noreply@blogger.com (Engineering Quality Solutions) — Thu, 07 Feb 2013 22:00:00 +0000

You’ve probably noticed that hardness is sometimes reported on your sheet metal certs (and if you see it, you are likely paying for it, probably a few dollars a ton). If you are using mild steel that’s about 1.5 mm (0.060”) thick, it’ll probably be in the mid to high 70s if it’s measured on the Rockwell B scale. But what does this really mean?

Simply put, hardness is a measure of the resistance to indentation. Of course, different materials have different performance, but the test result also depends on what kind of indenter is used (size/shape/material) and how much force is used to push it into the sheet metal. These testing parameters determine what scale is used to report results.

Rockwell hardness values are determined using a two-step process. First, the indenter (either ball- or cone-shaped) is pushed into the surface until the desired pre-load (also called “minor load”) is reached (10kg for the B and C scales, 3kg for the N and T superficial scales). This small initial penetration seats the indenter and provides a reference depth. An additional “major load” is applied, which results in deeper penetration into the sheet metal surface. The major load is then removed and the minor load is re-applied. The difference between this depth reading and the reference depth is used in the Rockwell hardness calculation, and is “d” in the equation for the Rockwell B scale:
HRB = 130 – ( d / 0.002mm )

This calculation shows that if a Rockwell B value of 80 is measured, there is a 0.10mm difference in depth between the minor and major load, and for HRB65, there is a 0.13mm penetration. Put another way, there is only a 30 µm difference in penetration depth between readings of HRB65 and HRB80. As a point of reference, the thickness of human hair is on the order of 100 µm (0.10mm).

The Brinell hardness test involves applying a specified load using a hardened steel or tungsten carbide spherical indenter of a specified diameter (typically 1mm to 10mm). The Brinell hardness number is calculated by dividing the load applied by the hemispherical surface area of the indentation. Due at least partially to the relatively high loads and to the challenges of measuring a curved surface area, Brinell testing is typically not used for sheet metal.

Like Brinell testing, the Vickers hardness number is calculated by dividing the applied load by the surface area of the indentation. However, a Vickers microhardness test is typically done with significantly less force than a Brinell test, using a diamond indenter having a square cross-section. Built into the Vickers microhardness test machine is a microscope that allows for more precise measurement of the diagonal cross-sectional lengths. By magnifying the surface, it becomes possible to target specific microstructural constituents (like martensite or bainite in Advanced High Strength Steels) or to assess the quality of heat treating or surface hardening operations.

Independent of the hardness scale used, a deeper, wider impression will allow for more accurate and representative readings. However, if the impression is too deep, then the platform that supports the test piece, known as the anvil, will influence the result. According to ASTM Standard E18 for Hardness Testing, to avoid this so-called “anvil effect,” it is necessary to have the indentation depth no more than 10% of the total test piece thickness. If your indenter or hardness test scale is inappropriate, you’ll likely see a shiny spot on the test piece underside where it was pushed into the anvil surface. If you see this, then you are testing the hardness of the anvil, rather than the hardness of your test piece. You’ll need to change your test conditions to produce a smaller, shallower indentation.

A brief example of the relevance of this part of the specification: Using the measurements shown above, you are in violation of the ASTM requirements if you are getting a Rockwell B hardness reading of 80 or less on sheet metal that is less than 1mm thick. Why? HRB80 means an indentation depth of 0.10 mm, and as the indentation depth increases, the hardness decreases. 10 times this indentation depth is 1 mm. Any greater penetration violates the 10x rule, and you are likely going to see the influence of the anvil in your results. The applied load on the Rockwell B scale is 100 kg. To produce a more shallow impression, you should switch scales, potentially to a 30T scale, where the applied load is 30 kg.

Something else to think about … In the first paragraph, I told you that your Rockwell B hardness was about 75 to 78. If I was able to do that without knowing anything about your coil, what does that tell you about the usefulness of hardness testing of sheet products? The bottom line is that hardness measures the resistance to indentation, but is a poor predictor of sheet metal formability.

Selected hardness scales	Indenter	Applied load
Rockwell – B scale	1/16” diameter ball	100kg
Rockwell – C scale	120° diamond cone with a 0.2mm radius spherical tip	150kg
Rockwell – 15T scale	1/16” diameter ball	15kg
Rockwell – 30T scale	1/16” diameter ball	30kg
Vickers	Square-based pyramid diamond indenter with a 136º included angle	Typically 10g to 1,000g
Brinell	Spherical indenter, with a diameter typically ranging from 1mm to 10mm.	Typically 1kg to 3000kg

Automotive Aluminum: Prices, Supply, and Demand

noreply@blogger.com (Engineering Quality Solutions) — Wed, 06 Feb 2013 22:10:00 +0000

Bloomberg article highlights:
* Morgan Stanley predicts a 29 percent gain in aluminum prices by 2018.
* At current aluminum prices, which are more than a third below 2008 highs, at least 30 percent of aluminum companies aren’t making money.
* The metal has failed to revisit the $3,317 a ton level reached in 2008, averaging about $2,200 in the past five years.
* The global surplus of aluminum may reach 1.8 million tons in 2013, as output rises to 51.4 million tons from 47.9 million in 2012.
* A switch to aluminum among U.S. carmakers could add as much as 40 percent to North American demand in coming years.

http://www.bloomberg.com/news/2013-02-05/carmakers-use-aluminum-over-steel-in-boost-for-rio-commodities.html

Danny Schaeffler
Engineering Quality Solutions, Inc. ... http://www.EQSgroup.com
4M Partners, LLC ... http://www.Learning4M.com

Making bottle crowns 50 microns thinner leads to multimillion dollar savings for SABMiller

noreply@blogger.com (Engineering Quality Solutions) — Mon, 04 Feb 2013 16:28:00 +0000

Global brewing company SABMiller has developed a bottle crown that
reduces the crown thickness to 0.17mm from a typical thickness of 0.22mm
to 0.24mm. This thickness change of 50 microns reduces the standard
crown weight from 2.38g to 2.14g, corresponding to a 360g reduction on
every pallet. Although this may not seem like a significant reduction,
SABMiller uses 42 billion steel caps a year. If implemented globally,
this change will reduce raw material costs by more than $12 million. The
technical challenge involved avoiding springback, which could have lead
to leakage and improper sealing.

http://www.sabmiller.com/index.asp?pageid=149&newsid=1638

Danny Schaeffler
Engineering Quality Solutions, Inc. ... http://www.EQSgroup.com
4M Partners, LLC ... http://www.Learning4M.com

Calculating Sheet Metal Thinning in a Formed Part

noreply@blogger.com (Engineering Quality Solutions) — Sat, 02 Feb 2013 02:20:00 +0000

Through my website, someone from a manufacturing company asked how to
calculate thinning in a sheet metal part made from 2mm thick high
strength steel. My response:

First, I assume the nominal or expected thickness is 2mm. But this is
just the aim thickness. The steel mill is allowed to ship product that
has some deviation from this gauge - maybe 1.85mm to 2.15mm as an
example. So you must get an accurate measurement of the actual starting
thickness. You should try to get it from the blank you will use to form
the part in question, or at least from an adjacent blank. The reason for
this is that there is likely a thickness variation down the length of
the coil. This normal and inherent variation occurs even when the
product is completely within specification. Similarly, you do not want
to make your thickness measurement at the coil edge. Due to a rolling
phenomenon called "crown," the edges of the coil are usually thinner
than the rest of the width. Again, this is allowed within most
specifications in that all minimum gauge measurements are to be made no
closer than 25mm from the coil edge (as an example). Across the coil
width, the thickest part is at the center width position of the master
coil. For this reason, I recommend taking your thickness measurement at
the 1/4 width or 3/4 width position.

The next step is to form the part. In the areas of interest on this
formed part, it is necessary to get an accurate thickness measurement.
Some companies will cut the part and use a micrometer to measure the
as-formed thickness, while others will use a calibrated ultrasonic
thickness gauge. The second approach does not destroy the sample, and
the part can be put back in for normal processing after it is measured.
If your area of interest has feature lines or small radii, it is
necessary to use the proper tools and techniques to get an accurate
thickness reading.

At this point, you have two measurements: the starting thickness of your
sheet metal (call that S) and the formed thickness of your part at the
location of interest (call that F). The percent thinning is calculated as
T% = 100 * (S-F)/S

If you have accurate measurements, you can have confidence in your
results. Best of luck!

Danny Schaeffler
Engineering Quality Solutions, Inc. 4M Partners, LLC
http://www.EQSgroup.com http://www.Learning4M.com

Ultra High Strength Steel in 2013 Honda Accord

noreply@blogger.com (Engineering Quality Solutions) — Thu, 31 Jan 2013 00:34:00 +0000

2013 Honda Accord body structure is made of >55% high strength steel
with tensile strengths starting at 440MPa. Of this, >17% is ultra high
strength steel, with tensile strengths of 780MPa, 980MPa, and a
martensitic grade 1500MPa. This 2013 model represents the first use of
UHSS in the Accord lineup. In addition, the subframe has steel and
aluminum components that are joined via friction stir welding.

http://www.honda.com/newsandviews/article.aspx?id=6825-en
http://www.autofieldguide.com/articles/honda-accord-the-ninth-generation#

-Danny Schaeffler
Engineering Quality Solutions, Inc. 4M Partners, LLC
http://www.EQSgroup.com http://www.Learning4M.com

Automotive Lightweighting Workshop: February 12-13, 2013 in Ann Arbor, Michigan

noreply@blogger.com (Engineering Quality Solutions) — Tue, 29 Jan 2013 20:14:00 +0000

The next meeting of the National Research Council (NRC) Committee on
Fuel Economy of Light-Duty Vehicles, Phase 2 will be a lightweighting
workshop focused on lightweighting, mass reduction and their impact on
fuel economy. On the agenda for the meeting that will be held on
February 12-13, 2013 in Ann Arbor, Michigan are representatives from the
steel, aluminum, composites, and carbon fiber industries,

Agenda:
http://www8.nationalacademies.org/cp/meetingview.aspx?MeetingID=6475&MeetingNo=5
Registration:
http://www8.nationalacademies.org/EventRegistration/public/Register.aspx?event=70292DDD
Info: http://www.cargroup.org/?module=News&event=View&newsID=40

-Danny Schaeffler
www.EQSgroup.com www.Learning4M.com

The Ultimate Material for Automotive Manufacturing

noreply@blogger.com (Engineering Quality Solutions) — Fri, 25 Jan 2013 02:10:00 +0000

Cheap, strong, manufacturable, light-weight. That's all the auto industry wants. Of course, there is no single material that meets all of these qualifications, at least not under today's economics and technologies. The likely candidates – steel, aluminum, magnesium, and composites – each offer some benefits. Consider:

ArcelorMittal, the world's largest steel company, recently described the growing usage of Advanced High Strength Steel (AHSS) in automotive applications as: 6% in 2005; 9% in 2008; 14% (f) in 2014; 32% by 2020 (data provided by ArcelorMittal at the Platts/SBB Steel Markets Europe Conference in May 2012.)
AHSS is the cheapest advanced structural material at an average price of $1.70/kg, and is readily available. Carbon Fiber Reinforced Polymers (CFRP) are much more extensively used in aerospace, primarily because a 1 pound reduction is reportedly worth a $100 to $300 premium in this industry. While new aerospace models like Airbus' A350 and Boeing's 787 Dreamliner employ over 50% CFRP by weight, on average polymer composites constitute less than 2% of an automobile's total weight.
Based on a broad-based survey in Europe, Ducker predicts 150kg of automotive aluminum applications by 2015. However, to continue growth, it will be necessary to make significant inroads into the smaller cars (A- and B-class), which currently consume 103kg per vehicle. In Europe, these small cars make up 27% of the market, compared with 4% in the USA.
The global production capacity of magnesium at the end of 2010 stood at 1,320,000 metric tons. China held 82% of this capacity (1,080,000 MT), Russia holds 6% (80,000 MT), and the United States is the country with the third largest worldwide production capacity of 4% of the global amount, or 52,000 metric tons. (United States Geological Survey)
Industry experts estimate that carbon fiber can easily use up to 85-90 kg (200 lbs) per vehicle. For a single series model of 250,000 vehicles, that equates to 22,500 MT (50M lbs) of carbon fiber. That single series model would consume about one-half of today’s worldwide supply of carbon fiber. (Presented by Zoltek at the October 2010 SAMPE Fall Technical Conference)

Obviously, 350 words aren't enough to hit all the issues, but it's what we can start with. There will be more to come...

AHSS Applications in Automotive

noreply@blogger.com (Engineering Quality Solutions) — Thu, 24 Jan 2013 02:06:00 +0000

Sent: Tuesday, July 17, 2012 7:54:03 PM

The American Iron and Steel Institute (AISI) just released a 42 page report titled AHSS 101: Evolving Use of Advanced High-strength Steels for Automotive Applications. It's a great overview of the different grades of AHSS and their applications.

For a brief introduction, please see our 2-part series published by the Fabricators and Manufacturers Association (FMA) at www.TheFabricator.com. Part I describes the different grades, and Part II highlights some of the processing concerns stampers should consider in their designs and approaches.

Tool & Die Authority - May 2010

noreply@blogger.com (Engineering Quality Solutions) — Fri, 14 May 2010 21:15:00 +0000

The Tool and Die Authority May 2010 Newsletter contained these articles:

Linking to the Alternative-Energy Supply Chain, Part 2 : Joe Brown
Increasing Press Speed and Efficiency: Peter Ulintz
Tool and Die Futures Initiative—Brutal Facts, But Hope Lives On!: Bob Quinn
Effective Error Proofing: Drew Stevens

and from Danny Schaeffler of Engineering Quality Solutions (EQS)...
Problem-Solving Techniques: The Five-Whys (or, How to be a Wise Guy)

You've got good people in your organization, yet you still run into problems that impact production and profitability. When solutions are obvious, your people on the floor can solve problems without any extra help. But what happens when a problem arises that can't be fixed right away?

The Five-Why technique presented here is a method used to determine the root cause of a particular defect or problem. It involves tracing the chain of causality in direct and discrete increments, by questioning why the particular problem or observation occurred. The technique then leads to discovering the initial discrepancy or issue that started the process leading up to the failure.

Visit the Precision Metalforming Association website to learn how to subscribe!

Tool & Die Authority - April 2010

noreply@blogger.com (Engineering Quality Solutions) — Mon, 10 May 2010 12:13:00 +0000

The Tool and Die Authority April 2010 Newsletter contained these articles:

Keeping U.S. Manufacturers Linked to the Alternative-Energy Supply Chain: Joe Brown
Die Damage at Coil Change: Peter Ulintz
Lean Misperceptions: Bob Quinn
Proper Documentation for Troubleshooting and Cost Justification: Drew Stevens

and from Danny Schaeffler of Engineering Quality Solutions (EQS)...
Specimen Shapes Shown in Sheet-Steel Specifications (or, Know Where the Numbers Come From)

When you order steel, you define the grade by ordering to a certain specification, such as ASTM A653 when asking for hot dipped galvanized drawing steel. The specifications include details of the properties that must be met, such as composition and mechanical properties, along with thickness and flatness tolerances. The specification also includes a description of how these parameters are measured. Here we address the dimensioning of tensile test specimens.

Dogbone Dimensions

Historically, tensile-test specimen dimensions have been defined by the country or regional standardization organization from which the specifications were published. These include ASTM (American Society for Testing and Materials), JIS (Japanese Industrial Standards), EN (Europäischen Normen), BS (British Standards), DIN (Deutsches Institut für Normung) and SEW (Stahl-Eisen-Werkstoffblätter).

One of three standard test-specimen shapes typically find use for tensile tests; all have a basic dogbone shape so that failure occurs in the reduced-width section.

Visit the Precision Metalforming Association website to learn how to subscribe!

#autosteel: @DannyEQS Will Be Tweeting from the 2010 Great Designs in Steel Seminar on May 5, 2010!

noreply@blogger.com (Engineering Quality Solutions) — Wed, 05 May 2010 01:04:00 +0000

@DannyEQS will be live-tweeting from the Great Designs in Steel Seminar sponsored by AISI on May 5, 2010. I'll be using the hashtag #autosteel!

Talks on Advanced High Strength Steels from General Motors, Ford, BMW, universities, consultants, government organizations and more!

It's an annual event sponsored by AISI - and there's no charge to attend!

Nearly all of the presentations dating back to 2002 are on their website - you can see the tremendous scope and detail that gets presented every year.

And, no, I don't work for AISI. I'm just really impressed with what they provide the steel user community.

Tool & Die Authority - March 2010

noreply@blogger.com (Engineering Quality Solutions) — Tue, 04 May 2010 13:08:00 +0000

The Tool and Die Authority March 2010 Newsletter contained these articles:

How Detroit “Won the War”: Joe Brown
Tool Repair by Welding: Peter Ulintz
Compound Innovation: Bob Quinn
Preventing Nuisance Faults, Part 3: Drew Stevens

and from Danny Schaeffler of Engineering Quality Solutions (EQS)...
Loose Change Management Can Be Costly (or, Poor Record Keeping Can Lead to Costly Actions)

As a part evolves during the normal development cycle from CAD model to soft tool to hard tool to production-ready tooling, there can be many changes to the blank thickness, dimensions and shape, and sometimes even the type of material. It is imperative that a complete and detailed record of these changes be kept to document what was used at each step of the process, especially when the parts are involved in crash tests.

Here's the story of an important safety component — the windshield header for a convertible...

Visit the Precision Metalforming Association website to learn how to subscribe!

Technology Tips for Small Businesses: Send Live Tweets from Meetings you Attend

noreply@blogger.com (Engineering Quality Solutions) — Sun, 02 May 2010 22:50:00 +0000

Sara Morgan, owner of Custom Solutions, LLC and founder of the No Limits blog, sent out a solicitation for real world uses of technology geared towards Small Business Owners. She was kind enough to put my entry first on her growing list. Here's what I had to say...

You probably attend many meetings, conferences, and exhibitions specific to your business. By sending out tweets, you can position yourself as an expert in the field. You don't need to add commentary - just report the facts. Then, when people are searching for the well-known speakers, you'll come up on the search page as well. Visibility is critical to compete with the bigger players in your field.

Recently, I attended an industry conference on Sheet Forming of High Strength Steels. (You couldn't possibly be more specialized than that!) Rather than taking notes on paper, I tweeted them from my Blackberry - making sure each tweet had a specialized hashtag and some reference to the author and title. This left me enough characters for a brief comment. After the conference, I posted the tweets on my blog and my LinkedIn account.

Now, when people Google pertinent terms, I have a chance of coming up on the same page as the author. Will this additional recognition lead to business? I hope so, but it's been only a few weeks since the conference. However, being an independent consultant in a highly specialized field, I'll take any advantage I can get.

Tool & Die Authority - February 2010

noreply@blogger.com (Engineering Quality Solutions) — Sat, 01 May 2010 16:03:00 +0000

The Tool and Die Authority February 2010 Newsletter contained these articles:

Marketing Makes a Difference for Manufacturers — Part 2: Joe Brown
Tool Damage Caused by Sharpening: Peter Ulintz
Can Robotics Help a Tool and Die Shop? Part 2: Bob Quinn
Preventing Nuisance Faults, Part 2: Drew Stevens

and from Danny Schaeffler of Engineering Quality Solutions (EQS)...
What is Steel? … Part 4: Dual Phase Steels (or, The Shape of Things to Come)

Since the early to mid 1990s, dual phase steels have been available in Europe and Japan, and have been used in their bill of materials for vehicle production. Concurrent with the wider adoption of this family of higher strength steels, the overseas divisions of auto OEMs were forging closer ties with their US counterparts, and OEMs were pushing for common grades available worldwide. At the same time, fuel economy standards were getting more challenging to meet, and crash/rollover requirements were being raised. About 10 years ago, as a result of this perfect storm, domestic car companies pushed the North American steelmakers to develop and commercialize dual phase steels.

“Dual Phase” describes the steel microstructure – these grades have two phases: islands of hard martensite within a matrix of soft ferrite. As the martensite content increases, so does the strength. The most common dual phase steel grade has a minimum yield strength of 350MPa and a minimum tensile strength of 600MPa. In this alloy, there is about 10% martensite in the microstructure, with the remainder comprised of ferrite.

Visit the Precision Metalforming Association website to learn how to subscribe!

#SAEsteel tweets: Paper 2010-01-0990: “Improved Metal Stamping Lubricant Testing Using Controlled Formed Panels”

noreply@blogger.com (Engineering Quality Solutions) — Tue, 27 Apr 2010 20:27:00 +0000

... authored by Katherine Helmetag, Henkel Corp.; Elizabeth Siebert, Henkel Technologies

Lubricant Testing-Henkel: modified LDH-short stroke (no split, 200mm/min. Stamping forces lube into surface roughness
Lubricant Testing: used Autoform Sigma to determine friction. Want to ID deformation/pressures to simulate real world

#SAEsteel tweets: Paper 2010-01-0986: “A Practical Failure Limit for Sheared Edge Stretching of Automotive Body Panels”

noreply@blogger.com (Engineering Quality Solutions) — Tue, 27 Apr 2010 16:16:00 +0000

...authored by Dajun Zhou, Chrysler Technology Center; John Siekirk, Chrysler Group LLC; Bernard S. Levy, Colorado School of Mines; Changqing Du, Chrysler Group LLC; Xiaoming Chen, US Steel; John McGuire, Chrysler Corp.

Sheared Edge Stretching Failure Limit-Chrysler, US Steel,Colorado School of Mines: measure thickness easier than grid
Sheared Edge Stretching Failure Limit- uniaxial tensile strain at edge. Higher stains give crosshatched necking bands
Sheared Edge Stretching Failure Limit- in DP600, FLCo is 2x thinning limit. In TRIP700, it is 3x. For the data shown
Sheared Edge Stretching Failure Limit-previous post-laser cut edge comparison: thinning limit about 10% in both grade
Sheared Edge Stretching Failure Limit-shearing rather than laser cut drops thinning limit by about 3%

#SAEsteel tweets: Paper 2010-01-0981: “Extending Tensile Curves beyond Uniform Elongation Using Digital Image Correlation: Capability Analysis”

noreply@blogger.com (Engineering Quality Solutions) — Mon, 26 Apr 2010 18:19:00 +0000

… authored by Dan Zeng, Z. Xia, Ford Motor Co.

Extending Tensile Curves beyond Uniform Elong Using Digital Image Correlation-Ford; post unif stress strain data
Using Digital Image Correlation for Post Uniform Tensile Elongation; full field, small gauge length, hi accuracy
DIC for Post Uniform Tensile Elongation: smaller gauge length gives longer valid range of stress strain curves.

#SAEsteel tweets: Paper 2010-01-0976: “Experiences with Experimental Determination of the Yield Locus and its Evolution for AHSS

noreply@blogger.com (Engineering Quality Solutions) — Mon, 26 Apr 2010 12:07:00 +0000

... S. Sriram, ArcelorMittal Global R&D; Hong Zhu, ArcelorMittal Global R&D ; Benda Yan, ArcelorMittal Global R&D

Experimental Determination of the Yield Locus for AHSS-ArcelorMittal- no experimental evidence: costly, complicated
AHSS Yield Locus: considered tension shear &plane strain test. Balanced biaxial: cruciform,bulge,stacked compression.
AHSS Yield Locus: stacked compression method used. Friction at interface between platen & specimens was insignificant
AHSS Yield Locus: yield behavior up to 4% plastic strain is well represented by Von mises yield surface.

#SAEsteel tweets: Paper 2010-01-0980: “Advanced Material Characterizations and Constitutive Modeling for AHSS Springback Predictions”

noreply@blogger.com (Engineering Quality Solutions) — Sun, 25 Apr 2010 19:02:00 +0000

... authored by Hong Zhu, S Sriram, Benda Yan, Patrick Duroux, ArcelorMittal Global R&D

AHSS Springback Predictions-ArcelorMittal: predicted springback is highly dependant on material model chosen.

#SAEsteel tweets: Paper 2010-01-0434: “Bonding Studies between Fracture Toughened Adhesives and Galvannealed Steels with Zinc Coating”

noreply@blogger.com (Engineering Quality Solutions) — Sat, 24 Apr 2010 13:57:00 +0000

... … authored by Jagdeesh Bandekar, Dow Automotive Systems; Michael R. Golden, Dow Automotive; Greg Meyers, Dow Chemical; Benda Yan, ArcelorMITTAL; Jeffrey L. Fenton, Dow

Bonding Fracture Toughened Adhesives & GA Steels-Dow/ArcelorMittal- perception is FTA isn't needed b/c Zn layer delam
FTA-GA Steel Bonding: orig study was 20 yrs ago on EDDS (weak grain boundaries). Not with AHSS-it's cohesive failure.
FTA-GA Steel Bonding: Fracture Toughened Adhesive has better energy absorption/impact than typcal hem flange adhesive

#SAEsteel tweets: Paper 2010-01-0436: “Application of a High Speed Camera for Video Extensometry during High Temperature Tensile Testing”

noreply@blogger.com (Engineering Quality Solutions) — Fri, 23 Apr 2010 20:53:00 +0000

... authored by Raj Mohan Iyengar, Severstal North America Inc.; Frank Jenner, Ohio State Univ.

Video Extensometry during High Temp Tensile Testing of Al Coated Boron Steel: OSU/Severstal- props not directional
High Temp Tensile Tests of Boron Steel: surface roughness increases with coating diffusion time and saturates
Hi Temp Tensile Tests of Boron Steel: challenge- gripping specimen, thermal expansion, hard on equipment, non-contact
Hi Temp Boron Steel Tensile Test: used multiple reference markers for hi speed camera tracking (used welding wire)
Hi Temp Boron Steel Tensile Test: low accuracy at low strains. Strain rate dependence more significant at hi temps.

#SAEsteel tweets: Paper 2010-01-0444: “Tensile Deformation and Fracture of TRIP590 Steel from Digital Image Correlation”

noreply@blogger.com (Engineering Quality Solutions) — Fri, 23 Apr 2010 11:13:00 +0000

... authored by Vesna Savic, Louis Hector, Keith Snavely, Jason Coryell, General Motors.

Tensile Deformation of TRIP590 Steel from Digital Image Correlation-GM: 1.5mm thick, 500 frames captured per test.
Using DIC for TRIP590 tensiles: up to 10% difference in true strain at UTS depending on orientation re: rolling dir
Using DIC for TRIP590 tensiles: How much of variation in flat sheet properties make a difference in final vehicle?