To leverage the rapidly-increasing demand for turbochargers into an increase in the number of orders, it is important to shorten the development cycle and reduce the time required before presenting a prototype to the customer. The interface shapes of the compressor cover and turbine housing, both of which are parts of a turbocharger, are specific to each car type. Moreover, as these parts are manufactured by molding, their production lead time is long. In an attempt to eliminate the need for molds and shorten the lead time, the applicability of metal additive manufacturing to compressor cover and turbine housing production was evaluated. In its application, the metal additive manufacturing element technologies introduced in Vol. 55, No. 2 of the Mitsubishi Heavy Industries Technical Review were employed. Handling the issues particular to compressor cover and turbine housing prototyping including the optimization of build conditions suitable for conventional casting materials, mechanical property evaluation of the built parts, evaluation of the internal flow path geometry and evaluation of performance as a turbocharger, Mitsubishi Heavy Industries Engine & Turbocharger, Ltd. (MHIET) has succeeded in reducing the lead time required for turbocharger prototyping to one-third or less.
