Hello everyone,
I just arrived in a new company, and I have a big problem. People here adjust peening time according to almen results, When I try to explain that only coverage is time relevant, and that the peening intensity is not linked to time ("intensity"), all the people here showed me saturation curves... I tried to explain with water: no success, with SAE quotation: no success, showed the "peening time paradox" article (great one by the way!): no success.
For me it's simple
https://www.electronics-inc.com/wp-content/uploads/solver.gifwith such saturation curve, my peening intensity is 9 minus 10%, if on the drawing of the part I need 8 almen, but my desired coverage is reached very soon, like time=2, I can work with no problems at 1T. Almen arc read by the worker who do control during the batch should be around 6.5 It's below the 8 specified on drawing, but we don't care, peening intensity is almost 9.
Am I crazy?
Main argument of my oponents is: almen arc due to residual stress, we want as much residual stress as possible, so if the almen does not display the wanted value, and continue arching when adding peening time, it means we should peen longer, as it clearly show that we can still provide residual stress to the plate, so why not to the product.
Do you know case where residual stress improve (deeper, better distribution, higher value) with longer exposition? (like 200, 300% coverage). I meanly know case which lead to the opposite result, as we risk overpeening...
Does almen plate arc only due to residual stress, or also other effects (maybe some effects due to the increasing surface).
Any idea to convince my peoples?
Have a nice day
