Free-cutting titanium material and preparation process thereof

A free-cutting titanium material, comprising a matrix component group and a free-cutting component group;

• the matrix component group comprises the following in percentage by mass:
• iron (Fe):
• 0-1.0%, nitrogen (N):
• 0-0.08%, hydrogen (H):
• 0-0.02%, oxygen (O):
• 0-0.50%, aluminium (Al):
• 0-8.0%, vanadium (V):
• 0-15.0%, and a balance being titanium (Ti) and unavoidable impurities;
• the free-cutting component group respectively refers to:
• a rare earth (RE) and sulfur (S) group, a copper (Cu) and S group, a zirconium (Zr) group, a carbon (C) group, a boron (B) group;
• in the RE and S group, RE is an element with the atomic number of 57-71 or a rare earth alloy composed of elements with the atomic number of 57-71;
• in percentage by mass, an addition amount of RE accounts for 0.5-2.4%, and an addition amount of S accounts for 0.1-1.0%;
• a mass ratio of RE to S satisfies:
• RE:S=n1:1, wherein n1=1.25-3.20;
• in the Cu and S group, Cu is added in the form of Cu powder or copper alloy;
• in percentage by mass, an addition amount of Cu accounts for 0.5-2.5%, and an addition amount of S accounts for 0.1-0.8%;
• a mass relationship between Cu and S satisfies:
• Cu=3S+m1, wherein m1=0-1.5%;
• an addition amount of the Zr group accounts for 0-3.0% in percentage by mass;
• in the Zr group, Zr is added in the form of zirconium-titanium alloy, and a mass relationship between Zr and Ti satisfies:
• Zr=0.048Ti−p, wherein p=0-2.5%;
• an addition amount of the C group accounts for 0-1.0% in percentage by mass;
• in the C group, C is added in the form of graphite or graphene;
• an addition amount of the B group accounts for 0-0.5% in percentage by mass;
• in the B group, B is added in the form of pure boron or ferroboron alloy.