The main strengthening ways of niobium are solid solution, precipitation and deformation heat treatment

In niobium alloy, tungsten and molybdenum can improve the strength at high temperature and low temperature, but too much of them will reduce the process performance.

Tantalum is a medium strength element and can reduce the plastic-brittle transition temperature of the alloy.

The other way of niobium alloy strengthening is to add titanium, zirconium and hafnium as well as a certain proportion of carbon to form dispersed carbide phase for precipitation strengthening.

In addition, these active elements can also improve other properties, such as titanium can significantly improve the anti-oxidation and process properties of the alloy; Hafnium and zirconium can improve the corrosion resistance of the alloy to molten alkali metal. Hafnium can significantly improve the oxidation resistance and welding performance of the alloy.

High strength niobium alloys generally contain a large number of solid solution elements (tungsten, molybdenum, tantalum, etc.) for solid solution strengthening, and precipitation strengthening is also used to make the alloys have high strength (see metal strengthening).The plastic machining of these alloys is difficult and the deformation parameters need to be controlled strictly.

In addition to Nb-10W-1Zr-0.1C alloy containing carbide precipitation strengthening phase, other medium strength alloys are added with medium solid solution strengthening elements to ensure excellent comprehensive performance.

As long as the right amount of titanium, zirconium and hafnium is added to the low-strength alloy, excellent machining properties can be guaranteed.