The invention discloses a low-pressure casting method of an aluminum alloy automobile hub. In the method, by optimizing alloy component design, adding a proper amount of Al-Ti-B-C refining agent and rare-earth modifying agent, low-pressure casting process parameters and thermal treatment parameters are optimized, so that the prepared automobile hub is provided with a tissue consisting of fine and uniform a dendritic crystal and fine and uniform worm-shaped or spherical silicon, and the performance of the aluminum alloy automobile hub is improved.

Low-pressure casting method of aluminum alloy automobile hub

The invention relates to aluminum-silicon-magnesium casted aluminum alloy and a casting process thereof. The aluminum alloy contains the following elements by mass: silicon 6.5 to 7.5, magnesium 0.40 to 0.60, titanium 0.10 to 0.30, strontium 0.01 to 0.03, iron no more than 0.20, copper no more than 0.10, zinc no more than 0.20, manganese no more than 0.10, beryllium no more than 0.01 and vanadium no more than 0.20, with the balance being aluminum. The casting process for the aluminum alloy comprises the following steps: putting A356.2 aluminum ingots in a furnace for melting; adding a modification material for refining; standing the product obtained in the previous step for a predetermined time and carrying out casting; sequentially carrying out solid solution, cooling, transfer and aging treatment. The invention enables the problems of low strength and elongation percentage of aluminum-silicon alloy and poor casting performance and corrosion resistance of aluminum-copper alloy and aluminum-zinc alloy to be overcome and tensile strength, toughness and casting performance of the aluminum alloy to be improved, and enables the aluminum alloy to have the advantages of low cost and good corrosion resistance.

Aluminum-silicon-magnesium casted aluminum alloy and casting process thereof

The invention provides an automobile wheel hub machining method. The automobile wheel hub machining method comprises the following steps of a smelting process, low-pressure casting, heat treatment, precision machining and surface coating. In the smelting process, silicon metal is added to aluminum liquid when the temperature of the aluminum liquid rises to 760DEG C, the silicon metal and the aluminum liquid are stirred for 25-30 minutes in an electromagnetic mode, wherein the content of the silicon metal is between 6.5% and 7.5%. When the aluminum liquid flows out of a furnace, AlSr alloy, AlTi5B alloy and magnesium are added to a flowing groove, wherein the content of Sr is between 0.008% and 0.012%, the content of Ti is between 0.1% and 0.2%, and the content of the magnesium is between 0.24% and 0.34%. In the low-pressure casting process, the aluminum liquid starts to flow out of the furnace under the temperature between 740DEG C to 750DEG C, refining and degassing are conducted on the aluminum liquid through high-purity nitrogen by 12 minutes, and then the aluminum liquid is conveyed to a low-pressure casting machine heat preserving furnace and is cast. In the heat treatment process, solid solution treatment, aging treatment and hardening treatment are conducted on a semifinished wheel hub formed after casting so as to obtain mechanical properties required by a wheel hub. The automobile wheel hub machining method can improve strength, hardness and forming of the wheel hub and meet requirements for safety performance of a wheel.

Automobile wheel hub machining method

The invention discloses a silicon carbide reinforced aluminum-based composite material and a preparation method thereof. The silicon carbide reinforced aluminum-based composite material is prepared from the following raw materials in percentage by volume: 20 to 25 percent of 325-mesh silicon carbide powder and the balance of 500-mesh Al-30Si alloy powder. According to the silicon carbide reinforced aluminum-based composite material, the silicon carbide powder and the Al-30Si alloy powder which have properly matched particle sizes are easily combined closely in the pressing and sintering process, defects such as air holes and cracks are avoided and the compactness of the composite material can be improved. In addition, by the preparation method of heating, pressurizing and keeping temperature stepwise according to set programs under the vacuum condition, slowly cooling together with a furnace to room temperature under the vacuum and high pressure conditions and removing the pressure, the metallurgical bonding of the reinforcement and the matrix is further improved, the defects such as air holes and cracks are avoided and the performance is high.

Silicon carbide reinforced aluminum-based composite material and preparation method thereof

The invention discloses an aluminum alloy automobile wheel hub composite reinforcement technology. Trace elements (comprising Mg, Ti, B, RE and the like) are added on the basis of original alloy components to carry out a reasonable component optimization, and effective purification, crystal grain refinement, deterioration treatment and finished product heat treatment are carried out in the melting process to simultaneously guarantee the good casting performance and the better mechanical performances of the alloy. The tensile strength, the yield strength and the elongation rate of aluminum alloy wheel hub products produced through utilizing the technology reach 262MPa, 179MPa and 9% respectively, and exceed strength performance standards in the Chinese wheel hub industry, so the technology has the advantages of certain practical production meaning, heat treatment period shortening, and substantial saving of the production cost.

Aluminum alloy automobile wheel hub composite reinforcement technology

The invention discloses a process for casting an 8356 type A356 aluminum alloy wheel and a heat treatment process. The process comprises the following steps of: a, adopting a metal mold low-pressure casting process, wherein the pouring temperature is between 690 and 735 DEG C, and the die preheating temperature is between 250 and 350 DEG C; b, performing thinning in a smelting furnace, adjusting the content of iron and silicon in aluminum liquid, performing metamorphosis in a refining pack and nitrogen-blowing refining outside the furnace, and adjusting the content of magnesium, strontium andtitanium in the aluminum liquid; c, adding a cooling pipe to a thick and big part of the wheel to perform quick cooling, and filling insulation cotton on the periphery of a side die to slow down the cooling speed of the middle part of a wheel rim so as to realize solidification in order; and d, cooling a wheel cast and putting the wheel cast into a heat treatment kiln to perform solution and aging treatment. In the process, suitable pouring temperature and reasonable cooling measures are adopted to effectively realize feeding and shrinkage of the cast; in the pouring process, a filter screen is arranged at a riser tube to effectively prevent inclusions; and through the control of key technological parameters, the product quality of the 8356 type A356 aluminum alloy wheel cast is ensured.

Process for casting aluminum alloy wheel and heat treatment process

The invention relates to a preparation method of a particle-reinforced aluminum-base composite material, which comprises the following steps: a. mixing reinforcing particle powder and aluminum alloy powder according to a ratio of (7-11):1; b. filling the evenly mixed powder into a hot pressing sintering furnace, carrying out hot pressing sintering at a heating rate of 10-20 DEG C/min under a hot pressing pressure of 20-30 Mpa, keeping the temperature and pressure for 20-40 minutes when the temperature ascends to 400-500 DEG C, and carrying out furnace cooling; and c. taking aluminum or aluminum alloy which is three times of the sum of weight of reinforcing particle powder and aluminum alloy powder, smelting, adding the blank obtained in the step b after the mixture is molten, and treatingfor 10-20 minutes by using a 25% Na2SiF6+75% C2Cl6 refining agent matched with a rotary degasifier after the blank is completely molten in the aluminum liquid; adding a refiner Al-5Ti-1B interalloy which accounts for 4 wt% of the aluminum or aluminum alloy at 720 DEG C, keeping the temperature for 5-10 minutes; and standing for 15 minutes, and pouring into an ingot mold.

Youchao Wang

Papers

Process for casting aluminum alloy wheel and heat treatment process

Preparation method of particle-reinforced aluminum-base composite material