Hello All,
I'd like to gather some thoughts on interpreting tensile test charts. I've seen a number of examples online as well as on textbooks but as I've started reviewing real world examples, as is often the case, there are some chart behavior that I can't quite explain. I've attached a photo of an example from a metal specimen, "tensile chart example" (excuse the blacked out areas - had to redact certain sensitive info). On the picture, note the vertical line at the point of fracture. Our tensile testing s/w interprets the load at which fracture occurs at the top of this line - 4450 lbf. Being a straight vertical line, it appears this is when the extensometer was removed, however load continued to be applied. The s/w further interprets this as UTS = 86 ksi.
From what I know with tensile charts, it looks to me that the load at which fracture occurs should be closer to 2880 lbf - the point at which the curve ends. This brings the UTS down quite a bit.
Additionally, I'd like to know if anyone knows where I can obtain a document that shows a number of pictures showing typical errors in tensile testing and how they appear on a tensile chart (similar to the attachment, "extensometer slippage"). I'm thinking of collecting these images and putting them on our testing procedures as a quick guide in interpreting errors in tensile tests. Maybe even a poster I can put up in our lab.
Thanks.
I'd like to gather some thoughts on interpreting tensile test charts. I've seen a number of examples online as well as on textbooks but as I've started reviewing real world examples, as is often the case, there are some chart behavior that I can't quite explain. I've attached a photo of an example from a metal specimen, "tensile chart example" (excuse the blacked out areas - had to redact certain sensitive info). On the picture, note the vertical line at the point of fracture. Our tensile testing s/w interprets the load at which fracture occurs at the top of this line - 4450 lbf. Being a straight vertical line, it appears this is when the extensometer was removed, however load continued to be applied. The s/w further interprets this as UTS = 86 ksi.
From what I know with tensile charts, it looks to me that the load at which fracture occurs should be closer to 2880 lbf - the point at which the curve ends. This brings the UTS down quite a bit.
Additionally, I'd like to know if anyone knows where I can obtain a document that shows a number of pictures showing typical errors in tensile testing and how they appear on a tensile chart (similar to the attachment, "extensometer slippage"). I'm thinking of collecting these images and putting them on our testing procedures as a quick guide in interpreting errors in tensile tests. Maybe even a poster I can put up in our lab.
Thanks.
