Mechanical testing must be on parts or on coupons ?
Mechanical testing must be on parts or on coupons ?
(OP)
In foundry some costumers ask to do the mechanicals tests on coupons however other costumers ask to do theses tests on parts.
What is the best method ?
Because if we do this on coupons it depends on the positions and the size of the feeders. If we do this on parts it's not esay to sacrifie a part only for extracting à piece for mechanical testings
What is the best method ?
Because if we do this on coupons it depends on the positions and the size of the feeders. If we do this on parts it's not esay to sacrifie a part only for extracting à piece for mechanical testings





RE: Mechanical testing must be on parts or on coupons ?
The method for conducting tests should be based on the applicable material specification. For example, ASTM A 703 or ASME SA 703 provide specific guidance for verifying mechanical properties of castings based on test bars or other coupons.
RE: Mechanical testing must be on parts or on coupons ?
These methods satisfy most of the inspectors.
However, in a few rare cases in the absence of sufficient test bars or if the section thicknes of the casting is too large so that the mechanical properties from keel block sample may not be a true representative, samples are drawn from a section of the casting. normally it is the heaviest section of the casting. But this issue will be discussed right at the beginning.
RE: Mechanical testing must be on parts or on coupons ?
The tensile bar is the lot-to-lot process control; coupons subsequently are not necessarily required in production lots unless there is a problem with the tensile sample. The end user should specify in writing when the job is awarded exactly what is required in production.
RE: Mechanical testing must be on parts or on coupons ?
The 'best method' is one that satisfies ASTM, ASME, etc. requirements, plus any additional customer requirements.
The specifications tell whether samples must be cut from cast parts, the required sample geometry and frequently give the sample location for different part geometries.
I suggest buying the Annual Book of ASTM Standards, Volume 01.02, January 2007, Ferrous Castings; Ferroalloys at
http:
Also buy the Steel Castings Handbook, 6th Edition http:/
The Steel Founders' Society Of America has free, downloadable supplements to the Steel Castings Handbook, 6th Edition. Go to http://www.sfsa.org, click on Publications, then Electronic Publications (Free). All seem useful; 'Test Coupons and Casting Properties' seems most relevant to this thread.
Also, from the LHS menu, click on Casting Design and Purchase. There are described general specifications on which customers & foundries must be in agreement.
RE: Mechanical testing must be on parts or on coupons ?