POWDER METALLURGICAL ARTICLES AND METHOD OF FORMING SAME AND OF BONDING THE ARTICLES TO FERROUS BASE MATERIALS

摘要

The present invention relates to powder metal articles that can be successfully welded to ferrous base materials. A formed part having an initial part density of at least 5.8 grams per cubic centimeter subsequently compressed is to at least ninety-two per cent (92%) of theoretical full density at a controlled area, including a contact area at which the part is adapted to be welded to the other material and at least a 0.025 inch wide margin of the surface laterally contiguous the contact area to a subsurface depth of at least 0.025 inch while retaining the initial part density throughout the balance of the article. Such increased densification is accomplished by applying inwardly directed, localized surface pressure against the controlled area of a formed powder metal part.