钨靶件试样的热等静压工艺试验研究

Investigation of Hot Iso-Static Press Process for Tungsten Target Samples

分别选用锆和不锈钢作为ADS固体钨靶的包壳材料,采用真空电子束焊制备钨锆及钨-不锈钢的小样品,在1 200、1 300、1 400℃和180 MPa下研究它们的热等静压(HIP)工艺条件。对HIP后的试样分别进行结合面微观观察、扩散层厚度、成分及其显微硬度的测试分析。结果表明：钨-锆及钨-不锈钢包壳管均结合紧密,未见间隙或微裂纹,在1 200和1 300℃下也未见钨晶粒长大；在钨-锆包壳管结合面处主要是锆向钨扩散,而钨向锆扩散则很少,在本试验条件下,扩散层深度为6～13μm；钨-不锈钢包壳管结合面处钨和铁的扩散明显,扩散层深度约为13μm,铬和镍的扩散较少,钨-锆及钨-不锈钢结合面的显微硬度测试结果也表明,在钨锆及钨不锈钢的结合面上存在着扩散层；在含吸氧材料Zr的1 300℃、180 MPa下进行等静压后,不锈钢包壳管部分区域熔化,因此,W-S．S．的HIP不能在含Zr的条件下进行,而不含Zr的1 00℃、180 MPa才适于钨不锈钢,1 300或1 400℃、180 MPa适合于钨-锆。

Zr and stainless steel（S. S. ） were selected respectively as the cladding materials of W target. The e beam weld was used to prepare the W Zr and W S. S. small samples for hot iso static press（HIP） process. The technology parameters of HIP were investigated at 1 200, 1 300, 1400 ℃ and 180 MPa, respectively. The micro morphology of the interface, diffusion depths and composition as well as their micro hardness were observed and determined. The bonding of W-Zr and W-S. S. is very well under the testing conditions. There is no any pore or micro-crack in the interface, and there is no grain growth of W below 1 400 ℃ either. The diffusion of Zr to W at the interface of W Zr is preferred during HIP process, and the diffusion depths under testing conditions are 6-13 μm. The diffusion of W and Fe is considerable at the interface of W-S. S. Its depth is about 13μm, and the diffusion of Cr and Ni is small. The hardness at the inter face of W-Zr and W S.S. shows that a diffusion layer is present for both interface. A part of stainless steel cladding was melted after HIP contained the oxygen absorber Zr at 1 300 ℃ and 180 MPa. Therefore, 1 200 ℃ and 180 MPa is suitable for W-S. S. without Zr, but 1 300 or 1 400 ℃ and 180 MPa is better for W-Zr.