Welded joints of the zirconium pipe were widely used in the chemical industry or nuclearÂ facility because their high mechanical properties and high corrosion resistance of zirconiumÂ material. To improve the mechanical properties of welded joint a method of TIG (Tungsten InertÂ Gas) welding with a suitable welding parameters were necessary used. Evaluation of strength andÂ microstructure of the welded joint will be used to improve the quality, strength and processÂ technology. This paper described the evaluation of the hardness, strength and microstructure of theÂ TIG welded joint of Zircalloy- 2 pipe. The welding was done for two kinds of samples using theÂ welding machine of the M80-3 model of the TIG (Tungsten Inert Gas) type, with the weldingÂ current of 30 and 35 Ampere/ second respectively. The hardness test was done by using the VickersÂ hardness scale. Testing of welded joint strength was carried out using the hydrostatic test byÂ measured the change of pipe diameters and observed the pipe brake according to the internalÂ pressure of 100, 200, 400 and 425 bars given into the pipe, and the microstructure test wasÂ observed by using the optical microscope. The hardness test showed that the maximum hardnessÂ number of 203 VHN was occurred at the heat affected zone (HAZ) area obtained. The result ofÂ hydrostatic test showed that there was not a change on the dimensions in the welded area up toÂ internal pressure test of 400 bars.
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