TABLE OF CONTENTS The results presented in the previous chapters show the complexicity of machining processes in powder metallurgy parts production. Regarding this fact, in the following chapter generalized data are given which should, however, be taken only as cutting recommendations because they do not - and cannot - include all cutting variants which may occur in machining of PM steels. The results are based on very broad laboratory and industrial experience which makes them acceptable as starting basis for machining of the respective materials. On the basis of these results, relating tool material and geometry as well as cutting conditions to the material properties of the part to be machined can be a contribution for cost effective elimination of often unexpected problems in machining of PM steels.
As will be shown later, in the listed data for recommended machining parameters there are hardly any informations about the role of machining aids and friction in cutting. The reason is that there are no general rules that apply for larger groups of PM materials, e.g. a correlation to the hardness as common for reasonable clear machining of wrought steels, due to the much larger set of parameters affecting the machinability of sintered steels.
The recommendations for machining in reality involve the data regarding the interactions between the workpiece material properties, the cutting method, the cutting tool material and geometry, the cutting conditions, and the required final shape and quality of the part which must be obtained under acceptable economical conditions.
In machining...
