NEWS

How to reduce the loss of die-casting molds through the control of aluminum alloy recycled materials

  • Browse number: ...
  • Release time: 2026-11-07

How to reduce the loss of die-casting molds through the control of aluminum alloy recycled materials
Recycled material is a commonly used raw material in die-casting production. Improper control not only increases the scrap rate of castings, but also accelerates die casting mold wear and aluminum adhesion. Xinfeng Machinery provides standardized control ideas.

1、 Safety threshold for blending ratio of recycled materials
Based on industry experience, it is recommended to control the mixing ratio of clean and oil-free sprue and riser materials within 30%. The proportion of recycled materials exceeds 45%, the content of hydrogen and impurities in aluminum liquid increases, the defects of casting porosity and slag inclusion increase, and the frequency of aluminum adhesion on the mold surface increases by about 28%. Small and medium-sized factories in Vietnam and India generally have a higher proportion of recycled materials, resulting in faster mold loss rates.

2、 The key process of pre-treatment of recycled materials
Recycled materials need to be sorted, degreased, and dried. Waste materials with moisture and oil stains entering the furnace will quickly increase the hydrogen content of the aluminum liquid. Impurities are formed by the combustion of oil stains, which adhere to the surface of the mold cavity and repeatedly accumulate to form a stubborn sticky aluminum layer, increasing the frequency of polishing and cleaning. The production of alloy wheel mold has strict requirements for the purity of aluminum liquid, and the proportion of recycled materials in the wheel production line is mostly controlled within 15%.

3、 Different processes have varying tolerances for recycled materials
The low pressure casting process is used for safety wheel hub components, which requires higher purity of aluminum liquid and stricter control standards for recycled materials than ordinary die casting. Die cast shell type non pressure bearing parts have greater fault tolerance space, but long-term high proportion reuse will still shorten the mold life. The raw material for metal injection mold is pre alloyed powder, and there is no traditional recycling mode for materials. The control system is completely independent.

4、 The chain effect of impurities on mold failure
The hard oxide inclusions inside the aluminum liquid continuously erode the cavity, forming abrasive wear and accelerating the expansion of surface fine lines. At the same time, the mixture will get stuck in the exhaust groove, frequently blocking the exhaust, requiring shutdown for cleaning, and disrupting the production rhythm. Many factories only focus on poor castings and ignore the continuous loss of die and mold due to impurities, which increases the cost of long-term tooling replacement.

5、 Difficulties in controlling the landing of overseas customers
Many small and medium-sized casting factories lack online hydrogen measurement equipment for aluminum liquid, making it impossible to quantify hydrogen content and relying solely on experience for judgment. Suggestions for synchronously matching aluminum liquid refining schemes when purchasing molds are easier to establish long-term trust. Google's "Aluminum Scrap Recycling for Die Casting" traffic is suitable for content layout aimed at foundry process engineers.

FAQ
Is the feed back material for sprues the same as that for scrapped parts? There are fewer impurities in the sprue and riser; The risk of impurities in scrapped parts with oil stains and coatings is higher, so use with caution.

What is the drying temperature set for the recycled materials? Keep at 120-150 ℃ for 2 hours to fully remove surface adsorbed moisture.

Do we need to increase the frequency of degassing due to the large amount of recycled materials? It is necessary to increase the rotor degassing time for each furnace to reduce the defects caused by hydrogen enrichment.

Can low-pressure casting of wheel hubs completely eliminate the need for recycled materials? The head auto parts factory produces new materials with the lowest defects, and the cost of raw material procurement increases synchronously.

Will the recycled material cause mold cracking? It will not crack directly, but impurities exacerbate wear and adhesion to aluminum, accelerating crack propagation.

Can ADC12 reflow and A356 reflow be mixed together? Mixing is strictly prohibited, as improper composition can directly result in the scrapping of batches of castings.

How to protect the storage of recycled materials? Covering to prevent rain and moisture, outdoor storage is prone to water absorption and oxidation.

What is the standard value of hydrogen content after degassing? The target control of airtight components is within 0.15ml/100g, and the stability of good products is better.

url: https://fr.zj-xinfeng.com/news/1399.html
Can't find any content

Get a Custom Product Proposal Online

Please fill out the form below to receive this for free.

Global Hotline:

+86-15356852630,13967513266