The current paper is related to the study of the microstructure and texture of two machinable lead-free brass alloys, namely CuZn42 (CW510L) and CuZn38As (CW511L), which were evaluated in the as-drawn and post heat treated condition. Electron backscatter diffraction (EBSD) was employed for the examination of the brass rods’ crystallographic properties in order to correlate the effect of post processing heat treatment on the evolution of phase structure and texture towards the interpretation of dynamic (impact) fracture properties. It is shown that α- and β-phase volume fractions, mean grain size, and grain boundary misorientation are the most influential factors altering the fracture resistance of single- and dual-phase brass alloy rods. The role of grain boundary engineering, through the formation of coincidence site lattice (CSL) boundaries and their evolution during thermomechanical processing, is of major importance for the design of the mechanical behaviour of new eco-friendly machinable brass alloys.
Bendability is a crucial property of automotive parts, which describes the ability of extruded profiles to be formed to shape, without the appearance of discontinuities that will have an adverse effect on the mechanical properties and their energy absorption capacity (crashworthiness). Anisotropic behavior exhibited by Al alloy extrusions has been documented due to the nature of the hot working process. In the present article an attempt is made in order to determine the main factors influencing bending properties in longitudinal and transverse to extrusion direction, which are also related with anisotropic behavior. Mechanical testing, microscopic examination and finite element analysis were applied in the frame of the current investigation. The findings were indicative that grain morphology and orientation (texture), especially on the surface zone of the extruded profiles, as well as morphology and distribution of the constituent particles are strongly related with formability.
16 June 2017 in Metallography, Microstructure, and Analysis