When the copper-rotating band of bullet is clad by means of tungsten inert gas (TIG) welding, the infiltrated cracks are usually appeared. The pure iron ( carbon content of less than 0. 04% ) was selected to produce rotating band as the cladding materials instead of copper. The cold-wire TIG welding, newly designed hot-wire TIG welding and vibration TIG welding were adopted to clad the pure iron to the 20 steel surface of bullet. The cladding speed of cold-wire welding was 1. 3 m/min, while the hot-wire welding was 1. 8 m/min, which is faster than cold-wire welding. The cladding speed of vibration welding was 1. 6 m/min. Besides, it can reduce the welding current by 10 A. The interface and cladding layer of welding joints produced by different welding methods were analyzed. The hot-wire welding made the grains connecting the interface and the cladding layer grow up, while the vibration TIG welding made them more smaller. The vibration welding can reduce the average hardness of cladding layer to HV160, or by HV15 or so compared with the other two methods. Shearing experiments show that the value of intensity on the connecting interface is much higher than its original intensity of bullet's cladding layer. From the results of shooting experiments, it can be seen that pure iron is another kind of feasible alternatives for copper as the cladding material.%针对铜弹带TIG堆焊过程容易出现界面渗透裂纹等缺点,选用软铁代替铜作为弹带的堆敷材料,采用冷丝TIG焊、新设计的热丝TIG焊及振动焊丝TIG焊在炮弹20#钢基体上进行软铁堆焊试验.冷丝焊接送丝速度为1.3 m/min,热丝焊接大幅提高送丝速度,达到1.8 m/min;振动焊接达1.6 m/min,降低电流10A.相对于冷丝焊接,热丝焊接使连接界面及堆焊层晶粒长大,振动焊接的破碎作用使界面及堆焊层晶粒变细.振动焊接使软铁堆焊层的平均硬度降到HV160,比其他两种方法降低HV15左右.连接界面处的强度值高于炮弹基体本身的强度.实弹发射效果良好,表明了软铁能代替铜作为弹带的堆焊材料.
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