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Yang Shanglei
Lu Xueqin
Lou Songnian
Institute of Welding,
Shanghai Jiaotong University,
Shanghai 200030, China
Zou Zengda
School of Material Science and Engineering,
Shandong University,
Jinan 250061, China |
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SURFACING
ELECTRODE WITH CRACKING RESISTANCE AND WEARABILITY
Abstract:
A new surfacing electrode is developed with cracking resistance and wearability based on high microhardness of TiC and VC, carbides of Ti and V are formed in deposited metal by means of high temperature arc metallurgic reaction. The results show the hardness of surfacing metal increases with the increase of ferrotitanium (Fe-Ti), ferrovanadium (Fe-V) and graphite in the coat. However, when graphite reaches the volume fraction of 11%, the hardness reaches its peak value, and when beyond 11%, the hardness falls off. As Fe-Ti, Fe-V and graphite increase, the cracking resistance of deposited metal and usability of electrode declines. Carbides are dispersedly distributed in the matrix structure. The matrix microstructure of deposited metal is lath martensite. Carbides present irregular block. When using the researched surfacing electrode to continue weld with non-preheated, no seeable crack or only a few micro-cracks can be observed in the surface of deposited metal. The hardness is above 60 HRC. The wear resistance is better than that of EDZCr-C-15.
Key words:
Surfacing welding Wearability Carbides |