Question

Would the four metals: nickel, titanium (well. the three boats I'm using would melt before this would at a pressure of the vacuum pump we have is capable of), iron, or chromium

would they react and cause corrosion to tungsten, molybdenum, or tantalum boats at temperatures of 1400 celcius or higher at vacuum pressures of 7.1x10^-2 torr? What would react and corrode with what? Why?

would any of these 7 metals (the three boats and the other four) react with what little oxygen is left in the vacuum chamber at a pressure of 10^-2 torr?

Please help and show where your sources are

ALSO where can I find a table for emissivity values at VARYING temperatures for tungsten, molybdenum, and tantalum?

Answer 1

The four metals given as Nickel, Titanium, Iron, and Chromium. These metals when we used for boats they are able to corrode itself for the iron is the heavy and some what low in case of the titanium and nickel and its too low to corrode for chromium. We have arranged temperature of almost 1400 degree celcius and 0.0071 torr , at this highest temperatures the boats may have tendensy to melt it mean the metals may be reached the recraystaization temperatures. They look like to formation of hot worked or cold worked properties depends on the metals.

These metals other than chromium react with the oxygen and forms an oxygenated metal than it looks like a strong metal towards corrosion. The metals which are close to the environment may leave its properties like hardenability especially when we use it at very low pressures. There is no source for me these words are in my own and these are written with my experience.