Thixoforging of particle-reinforced steel materials

The paper deals with a new process chain consisting of powder metallurgy (PM) and a subsequent thixoforging process. This innovative production process can increase the complexity of PM components and enable a high formability of brittle materials such as metal matrix composites (MMC). Compared to conventional materials MMCs feature improved mechanical properties and thus a high potential for various applications. In this investigation cylindrical raw parts, consisting of a steel powder and different proportions of titanium carbide particles, were produced by uniaxial powder pressing and sintering. Subsequently, the samples were heated up to the thixotropic (semi-solid) temperature range and valve parts were thixoforged by a backwards rod extrusion process. Finally, the particle-reinforced steel parts were characterised by metallographic analysis and hardness measurements.