DEVELOPMENT OF GUN-DRILLING MQL PROCESS AND TOOLING FOR MACHINING OF COMPACTED GRAPHITE IRON (CGI)

摘要

Compacted graphite iron (CGI) material offers great advantages in terms of higher performances, lightweight design, cost reduction and quality improvement for automotive applications, such as engine blocks. Unfortunately, tool life has been significantly lower in CGI material and especially in deep holes using standard gun-drill geometries. Hence, CGI applications have been limited. This research intends to study the machinability of CGI with the minimal quantity lubrication (MQL) process for gun-drilling large diameter holes. Tool wear and wear mechanism(s) were analyzed together with hole quality and part temperature using the methodology of rapid screening as an instrument to evaluate the MQL process and optimize CGI drills.