Graphite type coating paste for titanium and titanium alloy casting and preparation method thereof, and application of graphite type coating paste for titanium and titanium alloy casting

The invention relates to the technical field of casting, and provides a graphite type coating paste for titanium and titanium alloy casting and a preparation method thereof, and application of graphite type coating paste for titanium and titanium alloy casting. The graphite type coating paste comprises the following components: refractory aggregate, a binder, a bonding promoter, a dispersant and an antifoaming agent; the refractory aggregate is composed of zirconium dioxide, titanium dioxide and titanium hydride, wherein the mass ratio of zirconium dioxide to titanium dioxide to titanium hydride is (50-55):(40-45):(1-5). The refractory aggregate of the coating paste provided by the invention does not contain rare and precious metal oxides such as yttrium oxide and hafnium oxide, the graphite type coating paste is low in cost, stable in coating chemical property and high in high-temperature anti-burst performance, and can be applied to graphite mold casting of titanium or titanium alloy, and an obtained castin