Heat flow to the workpiece from a TIG welding arc
Heat flow to the workpiece from a TIG welding arc
复制标题
TIG 焊接电弧向工件的热流
DOI：
10.1088/0022-3727/6/18/310
复制
发表时间：
1973
期刊：
影响因子：
--
通讯作者：
A. Gick
中科院分区：
文献类型：
--
作者：
M. Quigley;P. H. Richards;D. Swift;A. Gick
在TIG焊接电弧(通常为1600W，16V，100A)中产生的热量中，只有不到一半传递到工件(阳极)。气体的对流、传导和辐射发生在整个弧区，但它们对总热量平衡的贡献相对较小。主要的阳极加热和冷却机制涉及表面的电子和空间电荷效应。这些电子效应在占主导地位的功函数(通常为45V)、电子热能传递(1V)和阳极下降(2V)中很明显，并且集中在受限的阳极电流点，因此可以认为它们是局域热源。从阳极点区域蒸发最强烈，带走了一些热量。然而，大多数蒸汽凝结在较冷的、被电弧覆盖的阳极表面的外部区域。通过这种方式，热量被重新分配，并在更大的区域内扩散。汽化效应解释了以前使用冷却铜阳极(其中80%的弧功率转移到金属)和使用实际的钢水焊接(低于50%的热传递)所进行的测量之间的差异。
Less than half of the heat generated in a TIG welding arc (typically 1600 W at 16 V, 100 A) is transferred to the workpiece (anode). Convection, conduction and radiation from the gas occur over the whole of the arc region, but they represent relatively minor contributions to the total heat balance. The principal anode heating and cooling mechanisms involve electron and space-charge effects at the surface. These electron effects are evident in the workfunction (typically 45 V) which is dominant, the electron thermal energy transfer (1 V) and the anode fall (2 V), and they are concentrated in the restricted anode current spot so they may be considered as a localized heat source. Evaporation is most intense from the anode spot region and carries away some heat. However, most of the vapour condenses on the cooler, outer regions of the anode surface covered by the arc. In this way, heat is redistributed and diffused over a wider area. Vaporization effects explain the differences between previous measurements with cooled copper anodes (in which 80% of the arc power is transferred to the metal) and ones with practical, molten-steel welds (less than 50% heat transfer).