Pieces with dimensional requirements, high performance and complexity obtained with the ISOPREC process

Considered for the fabrication of some alloy and stainless steel components, the ISOPREC process consists in densifying a metallic powder by Hot Isostatic Pressing in a shaped mould. After having been compacted, the mould is mechanically or chemically eliminated, and a piece with dimensional requirements is obtained. The important deformations which occur during powder densification cannot be experimentally anticipated (more than 30% of the initial volume is indeed eliminated). A simulation tool has been developed. Its database is progressively enriched by the properties of the different mould and powder materials, in order to increase the accuracy of the calculations. A comparison between the calculated and the experimentally fabricated pieces is presented. Some application examples of this process in the nuclear field are given (particularly with the stainless steel A316LN). High dimensional accuracy and mechanical properties are obtained for pieces with complex shapes. This process allows to reduce the costs and the production cycles of such high performance components. (O.M.)