Abstract: Provided are a collimator apparatus and a motion control method. The collimator apparatus includes a transmission assembly and at least two collimators. The transmission assembly is connected to the at least two collimators. The transmission assembly is configured to implement automatic switching of different collimators through rotation action.

Abstract: A silicon nitride ceramic material for a mobile phone rear cover and a preparation method therefor. The method comprises: using a mixture of a silicon source, a colorant, and a sintering aid as raw materials, mixing the raw material components, and performing shaping and sintering to obtain the silicon nitride ceramic material. The toughness of the silicon nitride ceramic material can reach more than 12 MPa·m1/2; the thermal conductivity thereof can reach 40 to 70 W/m·K; and a dielectric loss thereof is 10?4.

Abstract: A nickel-based alloy and a turbine component are disclosed. The alloy includes, by weight, between about 0.8% and about 1.3% hafnium, between about 5.7% and about 6.4% aluminum, between about 7.0% and about 10.0% cobalt, up to about 0.1% carbon, up to about 8.7% chromium, up to about 0.6% molybdenum, up to about 9.7% tungsten, up to about 0.9% titanium, up to about 0.02% boron, up to about 0.1% manganese, up to about 0.06% silicon, up to about 0.01% phosphorus, up to about 0.004% sulfur, up to about 0.02% zirconium, up to about 1.8% niobium, up to about 0.1% vanadium, up to about 0.1% copper, up to about 0.2% iron, up to about 0.003% magnesium, up to about 0.002% oxygen, up to about 0.002% nitrogen, and a balance nickel. The turbine component is a turbine bucket, a turbine nozzle, or any other suitable turbine component including the alloy.