Chilled Iron Castings products, Europe and the United States as early as the early 1920s has begun to develop, widely promoted in the sixties and seventies, eighties technology is fully mature. Chilled Iron Castings products with its low cost, high performance significant features, widely used in internal combustion engine.
Camshaft is an essential component of the internal combustion engine valve mechanism, its role is to control the movement of the valve, and according to a certain order of work and time to open and close, so its requirements must have excellent wear resistance. Now the commonly used camshaft in the use of carbon steel surface hardening and ductile iron quenching and other processes from manufacturing.
In foreign countries, 43% - 47% gasoline engine, diesel engine using Chilled Iron Castings as a camshaft material, Chilled Iron Castings generally as a camshaft material with its low cost, high performance significant features, has been widely used.
First, the performance and application of Chilled Iron Castings camshaft
The Chilled Iron Castings has good abrasion resistance and scratch resistance due to its high hardness carbide structure. The white layer in the Chilled Iron Castings is a series of lentils, which is a mechanical mixture of pearlite and carbides at room temperature and acts as a skeleton due to the large amount of carbides. Hardness is higher, and the ball in the lenticular play the role of oil storage. This rod of the creamer wear resistance, wear and oil storage of the reason, in the internal combustion engine industry has been widely attention and application.
Second, the technical parameters and technology
Chilled Iron Castings camshaft is based on the HT250 by adding a certain amount of alloying elements, through a special casting molding process from casting. The addition of alloying elements improves the hardness and overall mechanical properties of the camshaft base, greatly improving the wear resistance, and the wear of the Chilled Iron Castings is only about 45% of the 45 # steel and other other camshafts.
1, the mechanical properties of tensile strength ób> 250N / mm2
2, hardness HRC48--54
3, wear-resistant layer depth of 6 - 10mm
Third, due to the current use of ductile iron and 45 # steel using isothermal quenching or high frequency quenching to obtain martensite. After high-speed operation, cam peach tip parts of the early wear and tear, and Chilled Iron Castings using a special molding process, without heat treatment. All parts of the camshaft can get the required hardness values. Peach tip wear only ductile iron and 45 # steel 1/7, while reducing processing costs, improve the economy and so on.