Effect of temperature and hydrogen concentration on the lattice parameter of beta titanium

The lattice parameter of body centered cubic (bcc) beta titanium was determ ined as a function of temperature and hydrogen concentration using neutron diffraction, In pure titanium, the lattice parameter a = 0.331 nm at 900 de greesC and the thermal expansion coefficient kappa (T) = 13.8 X 10(-6) degr eesC(-1) over the temperature range 900 degreesC to 1000 degreesC, The solu tion of hydrogen in beta titanium is seen to expand the lattice but it has little effect on the thermal expansion coefficient. The dependence of the l attice parameter on atomic percent hydrogen was found to be linear over the hydrogen concentration range 0 to 30 at.%, as expressed by the hydrogen-in duced expansion coefficient K-H = 2.1 X 10(-4) nm/at.%H. (C) 2001 Elsevier Science Ltd. All rights reserved.