During our certified commercial shot peening process, each piece of shot — generally made of glass bead, ceramic bead, steel or stainless steel — that strikes the material acts as a tiny peening hammer, imparting to the surface a small indentation or dimple. To create the dimple, the surface of the material must yield in tension. Below the surface, the material tries to restore its original shape, thereby producing a hemisphere of cold-worked material highly stressed in compression below the dimple.
Nearly all fatigue and stress corrosion failures originate at the surface of a part, but cracks will not initiate or propagate in a compressively stressed zone. Because the overlapping dimples from controlled shot peening create a uniform layer of compressive stress at metal surfaces, controlled shot peening services provide considerable increases in part life.
In most cases of long-term failure, the common denominator is tensile stress. Tensile stresses attempt to stretch or pull the surface apart and may eventually lead to crack initiation. The shot peening process helps slow crack growth significantly in a compressive layer. Shot peening services offer the most economical and practical method of ensuring surface residual compressive stresses.
Compressive stresses are beneficial in increasing resistance to:
The maximum compressive residual stress produced just below the surface of a part by shot peening is at least as great as one-half the yield strength of the material being shot-peened.
While shot peening and blasting services both require shooting a stream of material against the surface of a part, they do not yield the same result. While shot peening is a process used to prolong the life of a part, shot blasting is done to clean and smooth a surface for processing.
We have several machines available for commercial shot peening services in Minneapolis, and for other businesses in the Twin Cities and greater Minnesota and Wisconsin area. We offer different sizes of shot for various applications and a certified team of experts to help you determine the best options for your metal parts.
Our dedicated team is prepared to be the one-stop shopfor Minnesota and Wisconsin-area businesses needing shot peening as well as other metal finishing services.