摘要 |
A surface of an article is heated and subjected to pressure by operation of a friction stir tool. The pressure of the face of the tool on the article surface, and the speed of rotation of the tool and of its progression along the surface of the article, are controlled to progressively hot-work a specified surface area. The face of the tool may be round and have a profiled, axially extending, smaller diameter pin for higher concentration of frictional heat and load and for plasticizing a surface layer of the workpiece. Such hot work may be applied for reducing surface porosity or for producing another change in the surface microstructure, or for effecting another change in surface material properties.
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