What additional benefit does adding rhenium to tungsten provide for the target?

Adding rhenium to tungsten enhances the strength of the target material at high temperatures. Tungsten alone has remarkable thermal properties and a high melting point, making it an excellent choice for use in x-ray tube targets. However, when rhenium is alloyed with tungsten, it significantly improves the mechanical strength of the tungsten alloy, especially under conditions of high temperature and stress.

This is particularly important in radiology, where the target material can become extremely hot during operation due to the absorption of energy from the electrons striking the target to produce x-rays. The addition of rhenium helps maintain the integrity of the target, reducing the likelihood of deformation or damage that can occur due to the high temperatures generated during x-ray production. Consequently, this enhancement in the material properties leads to more reliable and consistent performance of the x-ray tubes, ultimately improving the longevity and efficiency of the imaging equipment.