High Value Gray Cast Iron Material for Heavy Duty Diesel Cylinder Liners

摘要

The demand for higher output performance engines has lead to the increase of PCP (Peak Cylinder Pressure) and more aggressive engine designs for cylinder liners, mainly for new heavy duty engines developments where low cost components are been introduced. Such trends have generated demands to adequate the liner design by improving its material properties by changing its chemical composition, new materials data or even by introducing more accurate casting manufacturing process. Therefore, there is a clear tendency to development more and more alternative solutions that combine a certain technical high-value added and low cost. The most important material properties for cylinder liners are the ultimate tensile strength (UTS) and the fatigue tensile strength. Both parameters confer to the cylinder liners, especially for wet top flanged designs, the ability to survive under high mechanical and thermal load conditions even with reduced wall thickness. In this paper a low alloy GCI with a high UTS (minimum of 320MPa) and high fatigue tensile strength is presented, and its microstructure design is discussed. Moreover the results of mechanical properties and engine test in a Heavy Duty Diesel (HDD) engine are presented demonstrating that this cost-effective GCI material exhibits equal or even better performance than conventional high alloyed GCI material in production.