摘要
为了提高挺杆与凸轮这对摩擦副的耐磨性和可靠性,挺杆的材料选用了可淬硬合金铸铁,并且挺杆工作面的金相组织要求为梯度形式,即工作面从外缘处到中心处,碳化物的含量及硬度呈现从高到低的梯度趋势。为得到这种特殊的金相组织,我们从化学成分、孕育方法、熔炼和浇注规范、铸型等几个方面做了大量实验,终于获得成功。我们认为,化学成分、孕育剂的使用、熔炼及浇注规范、铸型的含水量等都必须严格控制,才能获得理想的有梯度的金相组织,其中过冷度是影响金相组织梯度的关键因素,特殊的SG孕育剂及孕育方法能有效地控制组织梯度。
In order to improve the abrasion resistance and reliability of the tappet and cam,the tappet materials had chosen hardened alloy cast iron, and the microstructure of the tappet working surface request form of gradient, that is the carbide content and hardness show a decline gradient trend on the surface from the outer edge to the center. To get this special microstructure, we learned and tried the chemical composition, norms of breeding methods, smelting and casting, casting model, and finally successed. We are of the opinion that, it must be controlled strictly of the chemical composition, the use of inoculant, melting and casting norms, the water content of casting model , and so on, in order to obtain the desired microstructure of gradient, in which, supercooling degree is the key factors that impact of the microstructure gradient, in addition, special SG inoculant and breeding method can effectively control the microstructure gradient.
出处
《内燃机与动力装置》
2009年第1期41-43,共3页
Internal Combustion Engine & Powerplant
关键词
耐磨性
合金铸铁
孕育剂
冷却速度
梯度
金相组织
Resistance to Abrasion
Alloy Cast Iron
Inoculant
Cooling Rate
Gradient
Micmstructure
