INKOV – Development of Innovative Piston and Valve Solutions Using Composite Materials in Marine Engines

As part of the subproject conducted within the INKOV collaborative research project, testing methods and specifications for quality assurance in the manufacturing process of marine engine components made of hybrid materials were developed and evaluated.

In this study, a new piston material based on a modified quenched and tempered steel was investigated with regard to its properties as a base material and as a friction-stir welding material for a large piston. The upper and lower sections of the piston were joined by friction-stir welding.

Tests were conducted on material specimens, friction-welded specimens, and specimens taken from a piston skirt. Dynamic tests were performed on large friction-welded pistons to evaluate the loads caused by ignition, inertia, and secondary piston motion. Experimental investigations involving strain and temperature measurements were conducted at the WTZ on a single-cylinder research diesel engine.

Through this research project, the suitability of the new piston material and the feasibility of friction welding large pistons were investigated and demonstrated.