A fundição de alumínio é uma técnica comum para fabricar carcaças de motores. Ela é eficiente o suficiente para superar qualquer nível de complexidade de projeto. O processo começa com o aquecimento do alumínio até seu ponto de fusão e sua inserção no molde. As carcaças de motor feitas de alumínio têm peso menor do que a média, duram mais e têm excelente condutividade térmica.

Vamos descobrir como o processo de fundição sob pressão produz esse produto usando ligas adequadas e suas aplicações e benefícios.

Benefícios da fundição sob pressão de alumínio para carcaças de motores

A fundição de alumínio para carcaças de motor é o processo ideal. Isso ocorre porque ele confere à peça a resistência e a durabilidade reais para resistir ao calor intenso.

Ligas como A380, ADC12 e A356 são os melhores materiais para uso em carcaças de motores. Isso se deve ao fato de a liga A380 ter uma grande resistência à tração de 310 MPa. Isso significa que ela pode suportar cargas pesadas.

Enquanto isso, o ADC12 é outra opção preferida, pois contém condutividade térmica de 96-105 W/m-K. Isso geralmente ajuda na dissipação de calor.

Já o A356 oferece não apenas peças de melhor qualidade, mas pode atingir alongamento de até 7%. Isso significa que ele pode resistir melhor ao impacto. De alguma forma, o alongamento depende das condições de tratamento térmico.

Todos esses recursos juntos fazem do invólucro de alumínio a escolha perfeita para aplicações automotivas, aeroespaciais e industriais.

Métricas de desempenho

Leve:

Quando se trabalha com alumínio, há uma característica de leveza nas peças. Por exemplo, essas peças são 60% menos pesadas do que as de ferro fundido. Isso mostra que é fácil manusear as carcaças do motor e transportá-las.

Alta precisão:

A fundição sob pressão assume perfis de produtos com eficiência e não cria variantes. Portanto, é basicamente uma boa opção para obter tolerâncias apertadas de até +/- 0,05 mm.

Condutividade térmica:

Os motores geram calor excessivo durante as operações. É por isso que o alumínio geralmente funciona melhor na carcaça do motor devido à sua boa condutividade térmica. Ele mantém os componentes frios. Por exemplo, a liga de alumínio A356 tem condutividade térmica de 150 W/m-K.

Condutividade elétrica:

Certos projetos de motores precisam de boa condutividade elétrica. Portanto, o alumínio também é bom o suficiente para essa propriedade.

Resistência à fadiga:

The material of motor housings, however, must handle repeated stress without breaking. For this, an alloy like A380 is suitable because it gives the required durability and lasts longer.

Análise de custos

Custo total de propriedade:

The upfront tooling cost of die casting becomes affordable because of what its long-run use does. Also, aluminum is not as costly as steel, and the casting process reduces waste.

Comparação com outros métodos:

The simplicity of the process, including fewer steps, makes it less costly than other methods of casting and machining.

Impacto ambiental

The die-casting process turns excessive material into reuse projects. Because aluminum is 100% recyclable and does not impact the environment much. Besides, its lightweight feature uses less energy, alternatively saving 25% fuel use.

Considerações sobre o projeto de carcaças de motor de alumínio fundido sob pressão

FEA e simulação

The processing of finite element analysis uses computer simulations. It improves designs and warns of upcoming defects before manufacturing. For example, stress points, heat flow, etc. So that the motor housing works efficiently.

Análise de tensão/deformação:

In the case of stress resistance,  simulations help manufacturers to identify weak points, even the reinforced areas prone to cracks. Additionally, using A380 alloy can aid in handling stresses around 150–200 MPa. That’s usually equal to car engine parts.

Análise térmica:

Simulations figure out heat movement capabilities while designing cooling structures. This is because motor housing must stay under 150°C without releasing excessive heat.

Redução de defeitos:

Simulation tools help eliminate defect chances, such as air porosity, by around 30–50%.

Projeto de sistema de canais e corredores

Gating systems serve as pathways for molten metal, flowing it toward mold. Their placement techniques affect the quality and strength of outputs.

Velocidade de fluxo:

The mold must be filled evenly, taking no more than 2 to 5 seconds. Excessive time increases the chances of air entrapment. That causes porosity (tiny holes)

Tipos de portões:

• Tab Gates: They are 2–5 mm thick and well-suited for large and heavy parts.
• Pin Gates: They are 1–3 mm wide. You can use them for thin-walled parts like motor housing covers.
• Overflow Gates: They can capture impurities. These gates also improve surface finish by 20%.

Controle de turbulência:

The designing of runners in a good way gives strong and smooth parts. It reduces porosity up to 20–30%.

Detalhes do projeto da matriz

The mold is an important component in die casting. It shapes molten metal into the final part. Their designing techniques really have a significant impact on output. For example, slides and cores in the die make stated features like cooling fins. But somehow, their 3 to 5-layer addition raises prices by 10 to 15%.

Similarly, placing ejector pins, giving them space between 10–15 mm apart, stops parts from bending during the process.

Speaking about cooling channels, they must be around 5–10 mm wide. That’s because a reduction in cooling time accelerates production speed.

Gerenciamento térmico

Effective thermal management is important during casting to stop overheating. For example, using heat sinks and fins in die design creates enough surfaces (50–70%) from where the excessive heat in the parts can escape.

Besides this, cooling channels should be used that have lower temperatures (20–30°C).

Additionally, the dies that are based on water cooling cool quickly from 600°C to 200°C, taking no more than 1-2 minutes. That further aids in cycling and production efficiency.

Processo de fabricação de carcaças de motor de alumínio fundido sob pressão

In a process like fundição de alumínio motor housing, the parts contain strong, stated finishing. That’s the result of using high-pressure molten alloy injection.

Casting machines feed the heated metal into the die using a piston and shot sleeve. Whereas the platen works as the holding tool. The toggle clamp tightly secures it.

Also, manufacturers give casting the required pressure via a gas/oil accumulator to make the process smoother.

Tipos de máquinas de fundição sob pressão

Máquinas de câmara quente:

Hot chamber die casting is well suited to alloys that do not contain high melting points. For example, zinc or lead. This is because high melting point metals like aluminum can damage machines’s equipment.

In the case of the hot chamber process, the manufacturers keep metal in a heated chamber. Wherein they pour it into the mold directly.

Máquinas de câmara fria:

These machines are ideal for casting moderate to higher melting point alloys. For example, aluminum, copper, titanium, etc. During this technique, manufacturers use separate chambers to melt selected alloy. Then they transfer it into the mold using a ladle. The machine works at 10–175 MPa injection pressure. So that the liquid metal spreads evenly inside the areas.

Força de fixação e tempo de ciclo:

The machine, however, uses 1,000–5,000 kN clamping force to close the mold tightly. Each cycle, including injection, cooling and ejection, is complete, taking no more than 30-120 seconds. That depends on part size and complexity.

Preparação de metal fundido

• Melting: This step is all about heating aluminum at 680–750°C in a furnace. The temperature must not be deviated from to avoid excessive oxidation and maintain fluidity.
• Degassing: This process is important in case of stopping molten alloy to absorb hydrogen from the air. The porosity occurs as a result. For this, degassing removes primarily hydrogen gas. It, therefore, prevents porosity and makes casting stronger.
• Filtering: There are impurities in metal, like oxides and non-metallic particles. That weakens the casting. This can be removed using a ceramic filter. Removal of impurities makes the metal more pure (15–25%) and creates a smooth finish.

Controle de temperatura da matriz

Die temperature management is necessary to eliminate defects and make better parts. For instance, cooling channels inside the die circulate water or oil. Preventing warping and shrinkage, they uniformly cool the metal.

Similarly, heating elements meet the necessities of certain molds to be warm. So they stabilize the temperature and avoid cracks.

Also, temperature control systems maintain die temperature at around 150–250°C. They reduce cold shuts or excessive shrinkage.

Automação em fundição sob pressão

Manuseio robótico:

Robot integration aids in cutting the overall cycle time (10–20%). Because they handle tasks beginning from melting to final products. This means there are fewer chances of error and results are more efficient.

Pulverização automatizada de matrizes:

To evenly spread lubricants onto the die, automation is helpful. It sprays the hidden areas and extends the life part by 15–30%.

Controle de qualidade e testes de carcaças de motor de alumínio fundido sob pressão

Testes não destrutivos (NDT)

Método de eco de pulso:

A transducer transmits ultrasonic waves into the housing. These waves reflect from defects when they do not pass through them. It focuses on parts nearly to indicate flaws in the metal.

Através do método de transmissão:

During this technique, the personnel at the two transducers on both sides of the casting. If there is a defect, the waves will not pass through or weaken.

Técnicas de inspeção

Inspeção por raios X:

These inspections analyze internal casting defects, like porosity or shrinkage. That could compromise actual performance. For example, ultrasound testing finds hidden cracks via high-frequency sound waves. Meanwhile, dye penetrant inspection helps locate surface defects with a certain dye.

Controle Estatístico de Processos (SPC)

The attached automation sensors in machines like SPC identify pressure, heat, cooling rates, and cycle times in real-time. You can immediately adjust the parameters for better output. Also, they help in reducing defects by 20–40% and material waste. It gives consistency in the quality of each batch.

Avaliação metalúrgica

• Microstructure Analysis: It helps recognize the actual grain formation and metal distribution for durability.
• Compliance Checks: This process ensures that the housing meets ASTM B85 standards for mechanical strength.

Aplicações e setores que utilizam carcaças de motor de alumínio fundido sob pressão

Automotivo:

Aluminum motor housings are used in electric vehicle (EV) motors. They keep working efficiently, containing less weight. Also, thermal management gets better, and the battery lasts longer.

Aeroespacial e drones:

Housing in drone propulsion systems stops impacting extreme temperatures and vibrations. It runs operations smoothly.

Maquinário industrial:

Many robotic arms, conveyor belts, and automated systems use motor housing. That’s because it gives structural integrity and dissipates heat for constant performance.

Energia renovável:

In varying weather conditions, these castings help maintain motor efficiency for wind turbines and solar tracking systems.

Equipamentos médicos:

The motor housing is increasingly in demand in medical equipments. That is because of its precision design, compact size and durability.

Conclusão:

The most important things about aluminum die-casting motor housing are its strength, durability, and excellent heat dissipation. This is why it is the best option for motor parts, where its lightweight feature improves energy efficiency. Additionally, improvements in alloys and techniques take it towards stronger, more efficient, and eco-friendly solutions.