Stainless steel lined composite steel pipe prepared by centrifugal-SHS process

The tension properties, thermal expansion coefficient, microstructure and t he causes of crack formation of the stainless steel layer in the composite pipe made by centrifugal-SHS process were investigated. It was shown that t he tensile strength is 316 MPa and the percentage elongation is 5-8%. The n onmetal inclusions make the stainless steel brittle. In the brittle stainle ss steel layer the crack is caused by the thermal stress. The stainless ste el mainly composed of austenite phase which grows in columnar grain in the radial direction of a carbon steel pipe and a thin ferrite layer was distri buted between the austenite phases. The intermetallic compound AlNi precipi tates in the ferrite phase and sigma-phase precipitates at the phase bounda rie between the austenite and ferrite. (C) 2000 Kluwer Academic Publishers.