Beta Processing of Ti6Al4V-Microstructure and Properties

摘要

Beta forging and/or heat treating of Ti-6-4 above the beta transus offers quite interesting advantages. In a first part of a study a near net shape technology by forging above the beta transus was developed. It allows cost saving by reducing both material input and machining cost by typically 30% and 50%,respectively. In this process the flow stresses are significantly reduced by increasing the forging temperature above the beta transus which results in low forging forces and an improved die fill behaviour. This process is particularly suited for relatively thin walled forging. It has been introduced for roller track forgings into three different airplanes. In a second part of the study beta annealed forgings with high damage tolerance were investigated. They were compared with beta forged as well as with beta forged and subsequently beta annealed forgings in order to find optimum property combinations. The presentation will describe the microstructure and property results and give an outlook on a range of applications.