金属型对灰铸铁和球铁力学性能的影响研究

采用铜合金金属型和铸铁金属型浇注灰铸铁和球铁Y形试块，加入不同量的Mn、Ti、Cu和Sn，研究金属型材料和添加合金对灰铸铁和球铁抗拉强度和疲劳强度的影响。结果发现：与采用铸铁金属型浇注相比，未加合金、采用铜合金金属型浇注的灰铸铁和球铁的力学性能略高。采用铜合金铸型浇注时，由于冷速较快，使石墨和基体组织细化的作用较强，添加合金元素改善力学性能的作用较为明显，而且反复浇注时，铜合金金属型的热应力较小。因此，灰铸铁和球铁采用铜合金金属型铸造比采用铸铁金属型有利。

An Investigation on Influences of Different Permanent Molds on Mechanical Properties of Gray and Ductile Iron

By pouring gray and ductile iron Y-specimens in both the copper alloy permanent mold and cast iron permanent mold and adding different amounts of Mn, Ti, Cu and Sn, the influences of materials of permanent molds and alloys additions on tensile and fatigue strengths of gray and ductile irons were investigated. It's found that, under the condition of no alloy additions, the mechanical properties of gray and ductile irons poured in copper alloy mold were some higher than that poured in cast iron mold. When pouring in copper alloy mold, due to its higher cooling rate which resulted in more strong effect to fine the graphite size and matrix structure, the effect of alloy additions to improve mechanical properties became more obvious. Moreover, the thermal stress of the copper alloy mold during repeat pouring was relatively lower. Therefore, it's more benefical to adopt copper alloy mold to pour gray and ductile iron casting than to adopt the cast iron mold.