Process route and acceptance of aluminum alloy subframe mold

Process route and acceptance of aluminum alloy subframe mold
Aluminum subframe reduces weight by 20% -30% compared to steel parts. The mold route is selected between low-pressure casting and extrusion welding, and the density is determined during acceptance inspection.
Weight loss benefits come from structural replacement
The weight of steel subframe is usually between 25-35kg, while aluminum alloy parts can be reduced to 18-25kg. The weight reduction range is 20% -30%, which directly contributes to the endurance.
The prerequisite for weight loss is structural redesign. Simple size replacement often fails to meet expectations and may result in insufficient rigidity.
Mold design should participate in the preliminary structural review. The distribution of wall thickness and the direction of reinforcement bars determine whether they can be stably formed in the future.
Low pressure casting is the mainstream route
The subframe has a complex shape and cavities, and the combination of low-pressure casting and sand core is most commonly used. The weight of a single item is mostly between 15-25kg.
The cost of molds often ranges from 400000 to 900000 yuan. The sand core tooling is calculated separately, usually accounting for 15% -25% of the mold cost.
The density of low-voltage components is relatively uniform and suitable for withstanding alternating loads. The X-ray judgment of key areas is recommended to be no less than level 2.
Applicable scenarios for extrusion welding routes
Extrusion and welding of profiles, suitable for sub frames with regular cross-sections and medium batch sizes. Low mold investment and short development cycle.
The weld seam is a weak point in fatigue. The quality of the weld seam depends on the welding process and subsequent heat treatment, and the mold only undertakes the extrusion mold and welding fixture.
This route has limitations on the degree of structural freedom. It is difficult to achieve extrusion routes at complex surfaces and variable cross-sections.
Key points of mold structure
The positioning of the sand core should be stable. The inner cavity of the subframe is long, and the sand core cantilever is large, which makes it easy to drift during filling. The recommended clearance for the core head is 0.1-0.2mm.
The pouring system should ensure sequential solidification. The thickness difference of the subframe wall is large, and the thick parts need to be cooled slightly, while the thin parts need to be insulated, with a temperature difference controlled within 15 ℃.
Xinfeng Mold will arrange the sand core support points and mold reinforcement ribs uniformly on the subframe mold to avoid interference between the two and insufficient local rigidity.
Three levels of acceptance content
The first layer is size. The installation hole position of the subframe is the core of the dimension chain, and the positional accuracy is usually required to be within ± 0.5mm.
The second layer is internal quality. X-ray or CT sampling of key areas, the shrinkage level shall be executed according to the drawings, and it is commonly required to be at least level 2.
The third layer is bench testing. Fatigue and stiffness tests are performed according to the vehicle load spectrum, with a typical cycle of 4-8 weeks.
Common Misconceptions
Misconception one is to only look at the price of a single item. The mold amortization and process yield of the subframe have a greater impact on the total cost.
The second misconception is to ignore heat treatment deformation. The subframe is long and can bend and deform up to 1-2mm after T6 treatment, requiring pre compensation or additional shaping processes.
Misconception three is the lag in sand core design. The sand core scheme should be determined in the early stage of mold design, and later changes will affect the entire pouring system.
Frequently Asked Questions
Q: How much weight can aluminum subframe reduce?
Answer: Common 20% -30%, requiring structural redesign.
Q: How much does the subframe mold cost?
Answer: Common costs range from 400000 to 900000 yuan, with additional charges for sand core tooling.
Q: How to choose between low-pressure and extrusion welding?
Answer: Low pressure is selected for complex cavities, and extrusion welding is optional for regular sections.
Q: What is the requirement for the positional accuracy of installation holes?
Answer: Commonly within ± 0.5mm.
Question: How much deformation does heat treatment cause?
Answer: The length can reach 1-2mm and requires pre compensation.
Q: How long is the bench test?
Answer: Usually 4-8 weeks, according to the load spectrum.
Recommended search keywords
Sub frame mold, aluminum alloy sub frame, sub frame low-pressure casting, automotive chassis structural components, sub frame mold manufacturers, customized structural component molds, low-pressure casting molds, sub frame weight reduction, aluminum alloy sub frame technology, sub frame mold prices