合金铸铁活塞裙的粒化退火

Graining Annealing of Alloyed Iron Piston Skirt

研究了退火热处理工艺方案对珠光体基合金铸铁活塞裙铸件本体和随炉附铸试棒的金相显微组织、布氏硬度值,以及随炉附铸试棒抗拉强度的影响。结果表明,合适的退火处理工艺能使铸件基体组织中的共析渗碳体发生粒化分解,在保证基体组织仍为珠光体前提下,降低铸件本体及随炉附铸试棒的硬度和抗拉强度,从而达到技术要求。

The influences of annealing heat treatment experiment schemes on the microstructure and mechanical properties of alloyed iron piston skirt and its test bars were studied. The results indicate that an appropriate annealing heat treatment process can let the eutectoid cementite in the pearlite matrix dissolute to granular cementite. Consequently, this annealing process decreases the piston skirt＇s hardness and tensile strength to some extent under the premise of almost all of the pearlites still remaining in the matrix, so as to achieve the technical requirments.