The working front of a target of ISIS Target Station 2 (TS2) is an assembly of a tungsten core clad with tantalum enclosed within a tantalum water cooling jacket. The aim of the tantalum cladding is to prevent the tungsten coming in contact with the pressurised and fast cooling water. However, a gamma spectral analysis on the cooling water after a target has failed shows the evidence of transmuted products of tungsten such as 175Hf, 172Lu, 182Ta and 187 W in the water. An electron beam weld joint on the tantalum cladding was identified as one of the areas of weakness. The penetration of the weld using the existing method was found to be inadequate and the grains of the weld line were found to be significantly enlarged. A failure of the cladding through the weld joint would cause the target life to be significantly shortened.

In order to improve the weld penetration, a study using different settings of the weld parameters such as weld current, oscillation and focus of the beam has been carried out. The study concluded that maximum weld penetration could be achieved using a combination of high weld power, sub surface focus of the electron beam and low material volume around the weld line.

A modification in the design of the front of the target has also been undertaken to ensure full penetration at the weld joints. This will prevent water coming in contact with Tungsten through the welding joint. In addition recent EB welding trials with a revised strategy, using multiple passes electron beams at different energies, have been successful in achieving 1350 μm weld penetration. An increase in the longevity of TS2 target and improvements in cooling water quality have been achieved after the modifications.

ISIS目标站2（TS2）的目标工作前部是包覆有钽芯的钨芯复合组件，钽包裹在钽水冷套中。钽包层的目的是防止钨与加压快速冷却水接触。但是，在目标失效后对冷却水进行的伽马能谱分析显示了水中钨的trans变产物（例如175Hf，172Lu，182Ta和187 W）的证据。钽覆层上的电子束焊接接头被确定为薄弱环节之一。发现使用现有方法的焊缝熔深不足，并且发现焊缝的晶粒明显变大。通过焊接接头的包层失效将导致目标寿命显着缩短。

为了提高焊接熔深，已经进行了使用焊接参数的不同设置的研究，例如焊接电流，梁的振荡和聚焦。研究得出的结论是，结合使用高焊接功率，电子束的亚表面焦点和焊接线周围的低材料量，可以实现最大的焊接熔深。

还对靶材前部的设计进行了修改，以确保在焊缝处完全熔透。这样可以防止水通过焊接接头与钨接触。另外，最近的EB焊接试验采用了经过修改的策略，使用不同能量的多次通过电子束，已经成功实现了1350μm的焊缝熔深。修改后，实现了TS2目标寿命的增加和冷却水质量的改善。