高纯稀土钇靶材和铜合金背板扩散焊接技术研究

Study on Diffusion Bonding Technology of Yttrium Target and Copper Alloy Backingplate

以高纯稀土钇材料及铜合金(C18000)材料为研究对象,研究了高纯稀土钇靶材和C18000合金背板在不同工艺条件下的扩散焊接性能。首先,通过Gleeble热模拟试验,研究了不同温度下稀土钇材料和C18000合金材料的屈服强度,以确定高纯稀土钇靶材和C18000合金背板的HIP扩散工艺;然后在不同的HIP焊接工艺下,研究异种材料间的扩散焊接强度。结果表明,在温度500℃及以下,稀土钇和C18000合金在110 MPa的压力下均不会发生明显的屈服变形;C18000合金的屈服强度明显高于稀土钇靶材,但是在400℃~500℃他们的硬度相差不大;高纯稀土钇靶材与C18000合金背板经过焊接温度450℃,压力110 MPa,保温3 h的扩散焊接后,扩散区深度约为12μm,焊接界面实现冶金结合,焊接强度达到81 MPa,满足8~12英寸大尺寸靶材的高溅射功率要求;当焊接温度提高至500℃,压力110 MPa,保温3 h的扩散焊接后,稀土钇和C18000间因形成金属间化合物相,导致焊接强度降低。

In this paper,the diffusion bonding properties of high-purity yttrium and copper alloy(C18000)was studied under different conditions.Firstly,the yield strength of rare-earth yttrium material and C18000 alloy at different temperatures was studied by Gleeble thermal simulation test to determine HIP diffusion process.Then the diffusion welding strength between dissimilar materials was studied.The results show that:Rare-earth yttrium and C18000 alloy will not yield deformation under temperature below 500℃and pressure of 110 MPa.The yield strength of the C18000 alloy is significantly higher than that of the rare-earth yttrium target at temperature below 500℃,but their hardness is similar at temperature 400℃to 500℃.The high-purity yttrium and C18000 alloy were put on 450℃/110 MPa hot isostatic pressing furnace for 3 hours,the diffusion depth is about 12μm,the welding interface achieves metallurgical bonding,the welding strength of sample can reach 81 MPa,meeting the requirements of high sputtering power of 8~12 inches target.As the intermetallic phase was formed under 500℃/110 MPa/3 hours HIP,the welding strength between high-purity yttrium and C18000 alloy decreased.