摘要: |
采用旁路热丝等离子弧作为热源,以中碳钢45钢板为基体进行电弧增材制造,并对该过程的温度分布特性进行研究。试验结果表明,旁路分流等离子弧增材制造过程中,熔覆层电弧熔池处温度最高,后方由于保护气的降温作用,后方温度先降后升;随旁路电流和主路电流增加,熔覆层整体温度升高,母材热输入增加;随增材速度的增加,熔覆金属整体温度降低,其分布的基本特征不发生改变。层间温度升高,熔覆层整体温度升高。熔覆层正面峰值温度从1175℃升至1902℃。增加层间等待时间,降低层间温度,有利于整体熔覆层温度的控制。熔覆层的显微组织均由块状铁素体和珠光体组成,随着层间温度的增大,熔池冷却时间增长,晶粒二次长大较为明显,珠光体含量随之减小。 |
关键词: 温度分布;等离子弧;旁路分流;增材制造修复 |
基金项目:国家重点研发计划资助项目(2018YFB1105804);上海市青年科技启明星计划(18QB1401700);装备预先研究项目(41404020102) |
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Study on the Temperature Distribution Characteristics of Medium Carbon Steel Additive Manufacturing Based on Bypass Shunt Plasma Arc Heat Source |
Zhao Huihui Zhou Jiafen Yin Yuhuan Miao Yugang Feng Xiaosong
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Shanghai Aerospace Equipments Manufacturing Co., Ltd.
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Abstract: |
The bypass hot wire plasma arc is used as the heat source, and the medium carbon steel 45 steel plate is used as the base metal to additive manufacture. The temperature distribution characteristics of the process are studied. The results show that the temperature in the molten pool of the cladding layer is the highest in the process of the bypass shunt plasma arc additive manufacturing, and the temperature in the rear decreases first and then increases due to the cooling effect of the protective gas. With the increase of the bypass current and the main current, the overall temperature of the cladding layer increases, and the heat input of the base metal increases. With the increase of the manufacturing speed, the overall temperature of the cladding metal decreases, and the basic characteristics of its distribution did not change. With the increase of interpass temperature, the overall temperature of cladding layer increases. The peak temperature of cladding layer increased from 1175℃ to 1902℃. The temperature of cladding layer increases with the interlayer time increasing, and it is beneficial to control the temperature of the whole cladding layer. The microstructure of the cladding layer is composed of massive ferrite and pearlite. With the increase of the interlayer temperature, the cooling time of the molten pool increases, the grain secondary growth is more obvious, and the pearlite content decreases. |
Key words: temperature distribution;plasma arc;bypass shunt;additive manufacturing and repair |