Researches of novel composite pistons for combustion engines

Novel composite material was worked out based on experiences and researches realized in the Institute of Aviation, the Lodz Technical University and PZL WOLA Company. Actually applied silumins on the pistons secure them high-quality for durability, low Rm and HB values at increased temperature, high hysteresis of the coefficient a during heating and cooling, high clearance between the piston and the cylinder, increased oil consumption, blowthrough and obtainment relatively low-power engine. Thereby works concerning elaborations of novel composite material based on the standard silumin with better from at present applied on the piston properties are presented. Novel composite material on the pistons has mechanical properties in the ambient temperature: Rm ≥ 400 MPa; Rp0.2 ≥ 330 MPa; A5 ≥ 3.5%; HB ≥ 130 and in the temperature 250°C: Rm ≥ 320 MPa; Rp0.2 ≥ 240 MPa; A5 ≥ 5%; HB ≥ 90. Metallographic and ATD researches, the researches of the hardness, the researches of Rm, Rp0.2 and A5, the researches of the coefficient of thermal expansion "α", engine researches were performed. Curves ATD and the microstructure the alloy are presented. Test results of the S12-U diesel engine engine are introduced too.