Heat Treat Stress Relieving

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Special vessel fabricated from Monel, a high nickel-copper alloy selected for its corrosion, stress relieved by Metlab. Stress relieving was done under a hydrogen-nitrogen atmosphere.

Heat Treat Stress Relieving  |  Facilities

Heat Treat Stress Relieving

Parts which have been heavily formed, machined, cut, or are fabricated by welding, have high internal stresses. The part or assembly can be made stress free by heating to a low temperature, where the stresses will be removed by thermal relaxation, without affecting the properties of the part. The resultant part will then be less prone to warp change dimensions during further processing or use.

Parts which have been formed, machined, cut, or are fabricated by welding, may have internal stresses. Subsequent machining or forming may cause the part to distort, or possibly crack in service. By heating the component to a temperature about 75°F below the transformation temperature, and holding for one hour per inch of thickness, allowing the entire part to reach this temperature, up to 90% of the stresses can be relieved. The resultant part will then be less prone to warp change dimensions during further processing or use. Since most parts which are stress relieved are subsequently machined, stress relieving is done in an air atmosphere. Metlab does have the facilities to stress relieve using a protective atmosphere, which is useful for complex aerospace weldments. Metlab also has the ability to stress relieve shafts and bars in the vertical position, which produces a stress free product which is relatively straight.

Typically, parts that benefit from stress relieving are large and complex weldments, castings which have had a lot of machining, parts with tight dimensional tolerances and machined parts that have had a lot of stock removal performed.

Facilities