NEW MECHANICAL PRETREATMENT PROCESS FOR THERMALLY SPRAYED ALUMINUM CRANKCASES

摘要

This new mechanical pretreatment method uses a special PCD insert which is clamped to a fine-boring tool. This insert consists of two cutting edges which are arranged symmetrically. The cutting profile reminds of a dovetail. The roughing process shows some strong advantages in comparison to conventional pretreatment methods like high-pressure water-jet roughing or chemical bond coats. The adhesive tensile strength is high (up to 57 MPa) and the cutting time is short (～10s / cylinder bore). The biggest advantage is that the fine boring machine can be used so that there is no need for an additional pretreatment machine and for changing the clamping of the workpiece. This means that process- and investment costs can be reduced.rnTherefore, the mechanical pretreatment method seems to be an interesting alternative to conventional pretreatment methods. Currently, different modifications of the cutting tool and the influence of coolant are tested to improve tool lifetime.