Molybdenum tungsten alloy
Molybdenum base alloy containing 25% and 30% tungsten, with good corrosion resistance of molten zinc, can be used to make molten zinc pump and electrolytic zinc electrode and filter molten zinc.
Temperature characteristic
Properties (1) The melting point of mo-W alloy increases with the increase of tungsten content. When tungsten content increases to 25%, the melting point of mo-W alloy increases about 200℃ compared with that of pure molybdenum. Therefore, the alloy composition can be selected in the range of 2620 ~ 3410℃ according to the operating temperature and the required melting point of the alloy. This advantage is also one of the advantages of Mo-W alloy to be widely used.
The lattice constant
The lattice constants and densities of mo-W alloys increase linearly with the increase of tungsten content. The hardness and strength of mo-W alloy increase with the increase of tungsten content
Hardness
The maximum room temperature hardness of the alloy is between 90% and 100% tungsten content, and its vickers hardness is up to 3530 ~ 3860MPa, which is more than twice as high as pure molybdenum. The highest high temperature hardness of the alloy is between 70% ~ 85% tungsten content. When the tungsten content increases from O to 40%, the tensile strength of machined mow alloy increases from 617MPa to 900MPa at room temperature.
Hardness value of molybdenum tungsten alloy ingot melted by vacuum arc
Strengthening mechanism The strengthening of binary Mo-W alloy is mainly solution strengthening and strain strengthening. When titanium, zirconium, niobium, carbon and other alloying elements are added to the alloy, the precipitation strengthening effect is obvious. Mo-20w, Mo-30W, Mo-50W, Mo-75W, Mo-90W, Mo-25W-0.1Zr-0.03c, Mo-25W-1.67Nb-10.37Ti-0.12ZI-0.18C, etc.
Hardness value of molybdenum tungsten alloy ingot melted by vacuum arc
Strengthening mechanism The strengthening of binary Mo-W alloy is mainly solution strengthening and strain strengthening. When titanium, zirconium, niobium, carbon and other alloying elements are added to the alloy, the precipitation strengthening effect is obvious. Mo-20w, Mo-30W, Mo-50W, Mo-75W, Mo-90W, mo-25W-0.1Zr-0.03c, Mo-25W-1.67Nb-10.37Ti-0.12ZI-0.18C, etc.
Molybdenum tungsten alloys can be used at higher temperatures than molybdenum or molybdenum alloys. For example, when molybdenum tungsten alloy is used as electrode, nozzle and thimble parts in bohe furnace for producing refractory ceramic fiber with high melting point, its service life is much longer than that of pure molybdenum metal products. Mo - 30W has higher resistance to zinc liquid erosion than pure molybdenum metal, and is mainly used in zinc liquid temperature tube, zinc liquid pump rotor and some corrosion resistant parts of zinc smelting furnace. Because of its high melting point, good ablative resistance and flame erosion resistance of solid particles, molybdenum-tungsten alloy can also be used in the gas rudder and guard plate of solid rocket engine. The common nominal composition of molybdenum tungsten alloy is Mo-30W, Mo-50W and Mo-85W. Molybdenum-tungsten alloy can be regarded as a transition alloy between molybdenum and tungsten. Therefore, the alloy can be used in a wide temperature range between molybdenum and tungsten.
