Yang Lin, Hua Junnan. Surface Cladding Coating Properties of AZ91 Alloy Engine Cylinder[J]. Special Casting & Nonferrous Alloys, 2016,36(4):349-353. DOI: 10.15980/j.tzzz.2016.04.004.
AZ91合金发动机缸体表面熔覆与涂层性能研究
摘要
对AZ91镁合金发动机缸体进行了表面等离子熔覆改性处理
对比分析了AZ91合金基材、TiB
2
-Al
2
O
3
和3种不同比例的Al与TiB
2
-Al
2
O
3
复合改性层的显微组织和物相组成
并对改性层的硬度、耐磨性和耐腐蚀性能进行了研究。结果表明
随着距离改性层表面距离的增加
显微硬度呈现逐渐降低的趋势
但改性层的显微硬度都高于AZ91合金基体
而TiB
2
-Al
2
O
3
改性层的显微硬度最高。随着熔覆材料中Al含量的增加
改性层显微硬度逐渐降低;随着磨损时间延长
基材与不同改性层的磨损质量损失都逐渐增加。3种不同配比的Al与TiB
2
-Al
2
O
3
复合改性层中w(Al)∶w(TiB
2
-Al
2
O
3
)=1∶2改性层的耐磨性能最好;经过等离子熔覆复合改性处理后的发动机缸体的耐腐蚀性能有所提高
其中
w(Al)∶w(TiB
2
-Al
2
O
3
)=1∶2时改性层的耐腐蚀性能最好。
Abstract
The surface of AZ91 alloy engine cylinder was modified by surface plasma cladding.The microstructure and phase constituent of AZ91 alloy substrate
TiB
2
-Al
2
O
3
and varied Al∶(TiB
2
-Al
2
O
3
)compound modified layer were analyzed
and the hardness
wear resistance and corrosion resistance of the modified layer were investigated.The results show that with the increase of distance from the surface of the modified layer
the micro-hardness of the modified layer is decreased gradually
however
the microhardness of the modified layer is the higher than that of AZ91 alloy substrate.The micro-hardness of the modified layer is decreased gradually with the increase of Al content
while the micro-hardness of TiB
2
-Al
2
O
3
modified layer has the maximum value.With prolonging wear time
the wear weight loss of the substrate and modified layer are increased gradually
and the wear resistance modified layer with w(Al)∶w(TiB
2
-Al
2
O
3
)=1∶2exhibits desirable.The corrosion resistance of the modified layer is improved compared with AZ91 alloy substrate