2004 Volume 12 Issue 2 Pages 78-84
There is a growing need to shorten automotive development time in order to respond promptly to customer requirements. In the basic material processing field of metal mold machining, technology has been developed to shorten machining time by proceeding in one processing step from castings with a 2mm stock allowance to the finished mold, by using a small ball end mill to machine all curved surfaces with a single tool. The first application of this technique was to molds for cylinder heads, which are among the principle components of automobile engines. In the machining of complex shapes such as those of cylinder head molds, conventional processes, which reduce the cutting speed where the cutting load is high, are inefficient and tend to produce vibration and chipping. Quality engineering was used to stabilize the process and find more efficient conditions. Recently, quality engineering has been used with great success to optimize cutting conditions by energy evaluation, but there have been few examples in intermittent cutting operations such as ball end milling. In this study, the basic function was taken to be a linear correlation between cutting volume and cutting energy, and optimal ball end milling conditions were found by analyzing intermittent cutting waveforms. Efficiency was improved by a factor of three with essentially the same machining accuracy as before.
