Influence of the hot isostatic pressing on the mechanical behaviour of CVD-coated hardmetals

CVD-coated hardmetals came into market almost thirty years ago. These materials perform well, where extreme difficult cutting conditions, such as interrupted cutting and precision works, prevail. In this work, two different grades have been investigated under monotonically increasing and cyclic loadings. For each grade two sets of samples were available, produced by means of two different sintering processes: Vacuum Sintering and Hot Isostatic Pressing. The aim of the work was to relate the mechanical properties to the sintering strategy. The mechanical testing revealed that, under both montonically increasing and cyclic loading, there were no significant differences related to the sintering process. This makes the more convenient conventional vacuum sintering more suitable for the production of the substrate hardmetal for CVD-coatings.