Thixotropy is characterized by a solid-like behavior at rest and a liquid-like flow when submitted to shear and advantage can be taken of this phenomena through two semi-solid processing routes; thixo-forming and rheo-casting.
The main advantages of thixo-forming are that it negates the need for handling liquid metal and the process can then by highly automated.
Compared to other materials such as aluminum, magnesium possesses a range of advantageous physical characteristics such as a much lighter weight, specific solidity and rigidity characteristics and good mechanical properties.
For use in design much information about processing remains unknown but deep draw testing has already shown that that an increase in elongation and a decrease in stress can be observed at elevated temperatures.
The Tube Hydroforming (THF) process is a relatively new manufacturing technology, which has been used in the past decade. THF offers potential alternatives in the use of lightweight materials and hence can have a great impact in saving energy in the automotive industry.
THF offers several advantages as compared to conventional manufacturing via stamping and welding.
One of these new processes is tube hydroforming and although the development of this process for the automotive industries is relative new, many process variables have been studied, including; friction, material properties, pressures and the displacement path during the process.
Hydroforming uses fluid pressure in place of the punch in a conventional tool set to form the part into the desired shape of the die.
The semi-solid processing of alloys is a relatively new commercial process which moved from a laboratory curiosity to a fully-fledged and viable manufacturing route in the 1970’s.
Lying between established solid and liquid state techniques, SSP allows the associated costs of solid state processing to be controlled and provides all the advantages of superior mechanical properties due to the precise changes in microstructure resulting from the slurry production steps.