The Corrosion Behaviour of Tantalum Tungsten Alloy
By alloying 2.5% tungsten with tantalum, the corrosion resistance of tantalum is not affected. In some cases, it can even be improved. The tungsten is itself highly corrosion resistant, is homogeneously dissolved and leads to improved strength.
For the comparison of the corrosion behaviour of the alloys with the base metals, static corrosion tests in aggressive media were carried out. In some cases, weight gains were caused by the absorption of oxygen. Larger quantities of the absorbed oxygen can cause brittleness and can destroy the metals by forming successive layers of scale on the surface. Pure tantalum and the tantalum alloy show such a behaviour in caustic solutions at elevated temperatures.
The corrosion tests lasted in general 70 days with the exception of those tests in which the samples were strongly attacked in a shorter time.
Materials with corrosion rates smaller than 0.25 g/m2/day are termed “very resistant”. Related to the corrosion behaviour of tantalum this would mean a thickness loss of less than 5.5 microns/year.
Materials with corrosion rates of less than 1.25 g/m2/day are termed “resistant”. In relation to the corrosion behaviour of tantalum this would mean thickness loss of less than 0.03 mm/year. Materials with corrosion rates greater than 10 g/m2/year are termed “unstable”.
Zhengzhou Sanhui Co., Ltd has been dealing in refractory metals, including molybdenum, titanium, zirconium, for 25 years. We offer standard or tailored metal products.
For the comparison of the corrosion behaviour of the alloys with the base metals, static corrosion tests in aggressive media were carried out. In some cases, weight gains were caused by the absorption of oxygen. Larger quantities of the absorbed oxygen can cause brittleness and can destroy the metals by forming successive layers of scale on the surface. Pure tantalum and the tantalum alloy show such a behaviour in caustic solutions at elevated temperatures.
The corrosion tests lasted in general 70 days with the exception of those tests in which the samples were strongly attacked in a shorter time.
Materials with corrosion rates smaller than 0.25 g/m2/day are termed “very resistant”. Related to the corrosion behaviour of tantalum this would mean a thickness loss of less than 5.5 microns/year.
Materials with corrosion rates of less than 1.25 g/m2/day are termed “resistant”. In relation to the corrosion behaviour of tantalum this would mean thickness loss of less than 0.03 mm/year. Materials with corrosion rates greater than 10 g/m2/year are termed “unstable”.
Zhengzhou Sanhui Co., Ltd has been dealing in refractory metals, including molybdenum, titanium, zirconium, for 25 years. We offer standard or tailored metal products.
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