Z-direction properties of steel plate

[salmon2]

thread404-187064

Just came cross the above thread because I have the same concern. Now it seems I found the answer and would like to share with everyone.

ASASTM A770 / A770M - 03(2007) Standard Specification for Through-Thickness Tension Testing of Steel Plates for Special Applications

I don't have a copy yet. Just from the title, seems like it is the standard for anyone who wants to know lamellar tearing resistance. Also, it seems it is to evaluate elongation and reduction of area in z-directly mainly. And I read somewhere else that YS and UTS won't change, much.

Welcome anyone to check in their experience and opinions.

 

[SJones]

For offshore structures, the issue is addressed in the materials standards. The designer identifies the need for through thickness properties and the standards, such as EN 10225, do the rest.

Steve Jones
Materials & Corrosion Engineer

http://www.linkedin.com/pub/8/83b/b04

 

[swall]

Not familiar with ASTM A 770, but I have done my own Z direction tensile testing by cutting a plate specimen and friction welding round bars on either side, then machining a standard .505 tensile specimen.

 

[Tmoose]

Mil spex often list separate "transverse" properties. Fatigue strength/endurance limit generally takes a big hit.

 

[Wrenchbender]

If x, y, and z are the rolling, width and thickness directions, resp., then mechanical properties, esp EL, RA, CVN and K_Ic, will be worst when the test specimen is aligned in the z direction. Yes, YS and UTS will not degrade as dramatically. (Main cause is mechanical 'texturing' of microscopic nonmetallic inclusions; secondary is maybe grain sizing and crystallographic texture.) The z is sometimes called the Short-Transverse direction.

"Very interesting indeed, but tell me, Mr. Faraday, of what use is this electricity?" "Sir, you will soon be able to tax it."

 

[ulyssess]

ASTM A770 contains requirements for the reduction of area when through thickness tensile test is carried out, not for elongation.
YS and TS in Z-direction may easily decrease to values lower than 80% of the value in transverse direction. This drop will be observed if the sulphur content is high (e.g. 0,020%) or if shrinking caviites, pores,.. are remaining (e.g. insufficient deformation ratio during rolling)