Charpy Impact Testing
Charpy Impact Testing
(OP)
Hello!
New to the forums and metallurgy in general. I have a question about impact testing (CAT 3). We have a material that we sent to a lab to be impact tested to meet 350WT CAT3 spec (for standard CSA G40.21-13). Prior to sending it out, I reviewed the mill test report for the chemical and mechanical properties to make an educated guess as to whether or not it would pass.
The chemical/mechanical properties met the 50WT spec as per the standard, but the impact test failed (by quite a lot). Are there any indications as to why a material would meet chemical/mechanical spec but not pass an impact test?
The material was 3/4" round bar. I have attached the mill test report with the chemical composition if you'd like to peruse it. The impact test results showed an average of about 8 ft*lb - well below the 20 required for a full specimen.
EDIT: If you're looking at the MTR attached, refer to heat # C112098
New to the forums and metallurgy in general. I have a question about impact testing (CAT 3). We have a material that we sent to a lab to be impact tested to meet 350WT CAT3 spec (for standard CSA G40.21-13). Prior to sending it out, I reviewed the mill test report for the chemical and mechanical properties to make an educated guess as to whether or not it would pass.
The chemical/mechanical properties met the 50WT spec as per the standard, but the impact test failed (by quite a lot). Are there any indications as to why a material would meet chemical/mechanical spec but not pass an impact test?
The material was 3/4" round bar. I have attached the mill test report with the chemical composition if you'd like to peruse it. The impact test results showed an average of about 8 ft*lb - well below the 20 required for a full specimen.
EDIT: If you're looking at the MTR attached, refer to heat # C112098





RE: Charpy Impact Testing
there are significant restrictions on the dimensions of the tested piece and the break point stress riser at the notch. If they were not met, the result can't be directly compared with a "standard" result.
RE: Charpy Impact Testing
RE: Charpy Impact Testing
If the MTR doesn't show Charpy test results, then the standard does not require it and by implication you should not expect it to pass.
"If you don't have time to do the job right the first time, when are you going to find time to repair it?"
RE: Charpy Impact Testing
RE: Charpy Impact Testing
RE: Charpy Impact Testing
What in the MTR am I looking for to determine the grain size?
RE: Charpy Impact Testing
RE: Charpy Impact Testing
RE: Charpy Impact Testing
The Purchaser, in addition to specifying the grade, specifies the required category of steel that establishes the CVN test temperature and energy level.