Method for manufacturing quasicrystal and alumina mixed particulate reinforced magnesium-based composite material

A method for manufacturing a quasicrystal and alumina mixture particles reinforced magnesium matrix composite, orderly comprising:

• manufacturing a quasicrystal and alumina mixture particles reinforcement phase, comprising
• preparing raw materials for manufacturing the quasicrystal and alumina mixture particles reinforcement phase comprising a pure magnesium ingot, a pure zinc ingot, a magnesium-yttrium alloy in which the content of yttrium is 25% by weight, and nanometer alumina particles, the elements having the following proportion by weight 40 parts of magnesium, 50-60 parts of zinc, 5-10 parts of yttrium and 8-20 parts of nanometer alumina particles of which the diameter is 20-30 nm;
• pretreating metal raw materials,
• cutting the pure magnesium ingot, the pure zinc ingot and the magnesium-yttrium alloy into metal blocks,
• removing oxides attached on a surface of each metal block, and
• placing the metal blocks into a resistance furnace to preheat and keep at 180° C. to 200° C. for 20 minutes to 30 minutes;
• pretreating the nanometer alumina particles, including
• putting the nanometer alumina particles into a beaker,
• adding absolute ethyl alcohol,
• placing the nanometer alumina particles in an ultrasonic cleaner to shock for 15 minutes to 20 minutes, and
• filtering out the absolute ethyl alcohol after standing, and drying in an oven at 590° C. to 610° C. for 5 to 8 minutes so as to completely evaporate the absolute ethyl alcohol where the ultrasonic cleaner has frequency of 20 KHz and power of 1000 W;
• flux-free smelting under a first shielding gas, including
• placing the pretreated pure magnesium ingot into a crucible of a melting furnace after the crucible is preheated to dark red,
• when the temperature of the crucible continues to rise to more than 400° C., continuously providing the first shielding gas to keep the subsequent smelting under protective atmosphere;
• homogenizing treating an alloy melt including,
• adding the pure zinc ingot after the pure magnesium ingot is completely melted at 700° C.,
• stirring and homogenizing the alloy melt after the pure zinc ingot is completely melted to separate oxides from the melt and to remove impurities on the surface;
• continuously heating the alloy melt to 760° C.,
• adding the magnesium-yttrium alloy,
• stirring to homogenize the alloy melt after the magnesium-yttrium alloy is completely melted;
• adding of the nanometer alumina particles including,
• cooling the alloy melt to 700° C., and
• coating the nanometer alumina particles with a magnesium foil pressed into the alloy melt and
• stirring for 3 minutes to get diffusion of the nanometer alumina particles in the alloy melt to be fully and uniformly;
• allowing to stand for 10 to 15 minutes after stirring,
• removing impurities and oxides on the surface;
• pouring the alloy melt into a metal mould preheated to 200° C. in advance and
• removing the quasicrystal and alumina mixture reinforcement phase after solidification;
• ball-milling the quasicrystal and alumina mixture reinforcement phase, including
• breaking the quasicrystal and alumina mixture reinforcement phase,
• adding alloy pieces into a planetary ball mill and
• milling the alloy pieces;
• and
• screening out particles having the size of 100 to 200 mesh using a stainless steel sieve to obtain the quasicrystal and alumina mixture particles reinforcement phase;
• manufacturing a particles reinforcement phase-magnesium alloy matrix melt mixture slurry, including preparing raw materials for smelting the magnesium alloy matrix comprising a pure magnesium ingot, a pure aluminum ingot, a pure zinc ingot, a magnesium-manganese alloy, a magnesium-silicon alloy and a magnesium-calcium alloy;
• the elements having the following proportion by weight 1000 parts of magnesium, 90 parts of aluminum, 10 parts of zinc, 1.5-5 parts of manganese, 0.5-1 part of silicon and 0.1-0.5 part of calcium;
• pretreating metal raw materials, including
• cutting the pure magnesium ingot, the pure aluminum ingot, the pure zinc ingot, the magnesium-manganese alloy, the magnesium-silicon alloy and the magnesium-calcium alloy into metal blocks,
• removing oxides attached on a surface of each metal block, and
• placing the raw materials into a resistance furnace to preheat and keep at 180° C. to 200° C. for 20 minutes to 30 minutes to remove moisture attached on the surface of each metal block;
• flux-free smelting under a second shielding gas, including
• placing the pure magnesium ingot and the pure aluminum ingot into a crucible and
• heating up to 700° C. to melt after the crucible is preheated to dark red,
• when the temperature rises to more than 400° C., continuously providing the second shielding gas to keep the subsequent smelting under protective atmosphere to prevent a magnesium alloy melt from oxidizing and burning;
• homogenizing treating of an alloy melt, including
• adding the preheated magnesium-manganese alloy at 700° C. after the metals are completely melted,
• adding the preheated pure zinc ingot sequentially at 700° C. after melting,
• stirring and homogenizing the alloy melt after melting to separate oxides from the melt and to remove impurities on the surface are removed,
• continuously heating up to 720° C.,
• adding the preheated magnesium-silicon alloy and the preheated magnesium-calcium alloy, thereby obtaining a magnesium alloy matrix melt after melting, and
• stirring to homogenize the magnesium alloy matrix melt;
• coating the quasicrystal and the alumina mixture particles reinforcement phase using an aluminum foil and
• pressing the quasicrystal and the alumina mixture particles reinforcement phase into the magnesium alloy matrix melt,
• mixing the quasicrystal and alumina mixture particles reinforcement phase with the magnesium alloy matrix melt to be homogenous by staged variable speed stirring, thereby obtaining the particles reinforcement phase-magnesium alloy matrix melt mixture slurry where the weight ratio of the quasicrystal and alumina mixture particles reinforcement phase to the magnesium alloy matrix is (4-8):100;
• allowing the particles reinforcement phase-magnesium alloy matrix melt mixture slurry to stand for 10 to 15 minutes, so as to separate oxides from the melt, and to remove impurities on the surface;
• casting ingot by pouring and extrusion, including cooling the particles reinforcement phase-magnesium alloy matrix melt mixture slurry to 700° C. in a crucible of the smelting furnace;
• preheating a steel mould in an extruder to 180° C. ˜200° C.;
• opening a cover of the smelting furnace, and
• aligning the cover with a pouring gate of the mould of the extruder, and
• pouring until a cavity is filled;
• performing die closing and extrusion by the extruder under extrusion pressure of 100 MPa for 15 to 20 seconds;
• by the pressure of a punch of the extruder, the particles reinforcement phase-magnesium alloy matrix melt mixture slurry in the cavity of the mould generates high pressure solidification and plastic deformation under mechanical static pressure of 100 MPa,
• cooling the ingot and the mould to room temperature naturally;
• opening the mould, and
• pushing out the ingot using an ejector pin device protruding out from a base of the extruder, thereby obtaining the finished product of the quasicrystal and alumina mixture particles reinforced magnesium matrix composite.