The meeting was called to order by John Bonnen who was acting in place of Russ Chernenkoff. The minutes of the meeting in LaConner, Washington on March 27-28 1995 were approved as written.
1996 SAE Congress. A one day technical session, entitled "Fatigue Research and Applications," is planned on February 28 as a part of the 1996 SAE International Congress. Fourteen presentations (13 papers) are in the session, which is being organized by Russ Chernenkoff and John Bonnen. Attached is the updated list of the days proceedings.
Status of Work in Progress
Composite Task Group -- Task group leader Mohamad El-Zein presented a synopsis of the testing and analysis to date. Mohamad indicated that he felt that the task group had fulfilled its mission, and, barring any further interest/ideas from the committee, he was prepared to end the task group activity in S-RIM. He reiterated the excellent correlation between predicted and experimental results for the S-RIM composite, and that he was confident that consistently good life predictions can be made. Mohamad presented the results of test which incorporated first a calibrated impact followed by either constant or variable amplitude fatigue. Mohamad mentioned that the unnotched specimens had little scatter in the lifetimes, and Ali Fatemi and Mohamad engaged in a discussion regarding the statistical nature of the S-RIM fatigue data. Ali Fatemi, Peter Kurath, and Mohamad El-Zein are the active members of this task group.
Powder Metallurgy Task Group -- Task group leader Steve Tipton indicated that not much progress was made since the previous meeting in LaConner, but substantial interest is now being shown by Burgess-Norton.
"ASTM E739 Fatigue Strength Modeling and the Impact on Structure Design" by Maolin Tsai of GM and Benda Yan of Inland Steel. Benda Yan discussed the statistical aspects of choice of independent variable on the regression of strain life curves.
Composite Task Group -- Mohamad El-Zein said that, since the S-RIM material is now exhausted, he would also like to explore the possibility of moving the task group focus onto fatigue of thermoplastics. He also mentioned that he would like to conduct fatigue tests of thermoplastics using "energy" based control.
Powder Metal Task Group -- Steve Tipton updated the group on the interest that Burgess-Norton has shown in working with FD&E on powder metal. They have committed to supplying material and machining. Ralph Stevens said that he has two students now working on PM and Burgess-Norton is supplying specimens for both constant amplitude fatigue properties (R=0.5 and 0.05), variable amplitude loading of a keyhole specimen, and, finally, fracture toughness specimens. Ralph invited any input from the committee with either the nature of the testing. He also asked for interested committee members to participate in a round robin testing program. There are still rounds and blanks available from the older PM materials.
New Business
Structural Adhesives -- no interest was shown.
Statistical Analysis of Material Properties -- Yong Lee from Chrysler mentioned that they had conducted a design of experiments study on spot welds in mild steel body sheet. The experiments involved tests on over 200 coupons, with coupon length, width, and nugget size. He was trying to get Chrysler to release the results of the study so that the committee could review them. Al Conle offered also some Ford spot weld data. Mohamad El-Zein will also look into a statistical analysis of the S-RIM data.
Respectfully submitted,
John Bonnen
313-322-9127
>From bonnen(at)fmsrlg.srl.ford.com Wed Mar 6 12:10:03 1996 Received: from fmsrlg.srl.ford.com by fmsrlb.srl.ford.com (4.1/Ford 2.0) via id AA28480; Wed, 6 Mar 96 12:10:02 EST Received: by fmsrlg.srl.ford.com (4.1/Ford 2.0) via id AA03760; Wed, 6 Mar 96 12:07:27 EST Date: Wed, 6 Mar 96 12:07:27 EST From: bonnen(at)fmsrlg.srl.ford.com (John J. Bonnen) Message-Id: <9603061707.AA03760(at)fmsrlg.srl.ford.com> To: conle(at)fmsrlb.srl.ford.com fax (313) 390-0514