The Technology and Commercialization of Thixomolding®

Abstract

The history of Thixomolding®, its technology and commercialization are reviewed along with recent evolution of new technology afforded by its metallurgical structure. Since Thixomolding was introduced in the early 1990’s, it has developed to more than 400 Thixomolding machines in the United States, Canada, Japan, China, Taiwan, Hong Kong, Malaysia, Korea, Germany, Belgium and France. Applications have been established in the electronics/communication, automobile, military, hand tool, medical and sporting goods markets. Thixomoldings principal advantages are in net-shaping, consolidation of parts, safety, environmental friendliness, mechanical properties and microstructure. The virtuous isotropic and fine-grained Thixomolded® microstructure has opened the door to derivative thermal mechanical processing for generating nanostructured Mg products of high strength/density along with improved ductility, fatigue strength, corrosion resistance and formability. This thermomechanical processing (TTMP) has been applied recently to the Thixomolded precursor to further refine the grain size and eutectic phases to nanometer sizes - providing yield strength above 300 MPa, fatigue strength of 150 MPa along with elongation of >10%. Alloys so processed include AZ50L, AZ60L, AM60, AZ61L, AZ70L-TH, AZ80, AZ91D, AXJ810-TH and Thixoblended® alloys of higher Zn content. Microstructure is related to processing and properties, as predestined by the Thixomolded microstructure. Fiber Metal Laminate composites based on this nanoMAG TTMP Mg product have demonstrated yield strength up to 900 MPa, with modulus of elasticity of 90 GPa.