Impact Extrusion

What is Impact Extrusion

Impact extrusion is a highly efficient manufacturing technique used to produce various products. Which is one of the fastest ways to get to near-net shape for many parts and components. Our process begins with a lubricated metal slug—also called a blank or a puck—that is placed in a die cavity. The metal puck is struck with a punch powered by a mechanical or hydraulic press. This forces the metal to flow into a shape or position almost instantly. In this post, we will cover its working principles, materials used, surface treatments available, advantages, disadvantages, applications, and future trends.

Como funciona a extrusão de impacto？

A extrusão por impacto é um processo de fabricação usado para criar peças metálicas ocas com paredes finas. Veja a seguir uma visão detalhada de como ele funciona:

TYPES OF IMPACT EXTRUSIONS

Reverse Impacting

In reverse-impact extrusions, metal flows backwards—in the opposite direction in which the force is applied—and then around the punch. The resultant part has a shape similar to that of the punch.

Forward Impacting

In forward impact extrusions, the punch pushes the material through an aperture inside the die. The punch fits into the cavity to the point that the metal cannot flow backward.

Combination Impacting

Combination Impacting is the combination of two impacting processes. Making more complicated shapes for parts Combination impacting pushes metal through a hole and as well backward around the punched.

The Basics of Impact Extrusion

Impact Extrusion is a precise and efficient machining process that produces high-quality cylindrical parts by rotating a workpiece against a cutting tool. This technology is crucial in various industries, from automotive to aerospace, due to its ability to create intricate and accurate components.

1. Colocação de material

O processo começa com um pedaço de metal, geralmente um material macio e dúctil, como alumínio, cobre, chumbo, zinco ou estanho. Essa peça é colocada em uma matriz, uma ferramenta que molda o material.

2. Movimento do punção

Em seguida, um punção, uma peça sólida de metal, atinge o projétil em alta velocidade e pressão. A força de impacto geralmente é gerada por uma prensa mecânica ou hidráulica.

3. Fluxo de metal

Após o impacto, o metal flui ao redor do punção e para dentro da cavidade da matriz, assumindo o formato da matriz. O fluxo do metal ocorre principalmente na direção radial, permitindo que o material se espalhe de forma fina e uniforme.

4. Ação do dado

A matriz, que é usinada com precisão para o formato desejado do produto final, confina e direciona o fluxo do metal. Dependendo do projeto da matriz, o processo pode criar várias formas, incluindo perfis cilíndricos, cônicos ou complexos.

5. Ejeção

Depois que o punção se retrai, a peça recém-formada é ejetada da matriz. Essa etapa pode envolver sistemas mecânicos adicionais para garantir que a peça seja removida sem danos.

The Basics of Impact Extrusion

Vários fatores afetam a qualidade e a eficiência do processo de extrusão por impacto:

Temperatura

Embora a extrusão por impacto seja geralmente um processo de trabalho a frio (realizado em temperatura ambiente), a temperatura do material pode influenciar suas características de ductilidade e fluxo. Às vezes, o pré-aquecimento do metal pode ser benéfico, especialmente para materiais mais duros.

Pressão e velocidade

A pressão exercida pelo punção e a velocidade com que ele atinge a lesma são fundamentais. Pressões mais altas e velocidades mais rápidas normalmente resultam em melhor fluxo de material e formas mais precisas, mas exigem maquinário e ferramentas robustos.

Lubrificação

Para minimizar o atrito e evitar danos à matriz e ao punção, a lubrificação é frequentemente aplicada às superfícies da bala e da matriz. Isso também ajuda na ejeção suave da peça final.

Vantagens e desvantagens da extrusão de impacto

Vantagens

Preparação:

Taxas de produção rápidas.

Utilização de materiais:

Mínimo desperdício em comparação com outros métodos.

Baixo custo:

Econômico para produção em larga escala.

Precisão:

Alta precisão dimensional e consistência.

Desvantagens

Investimento em equipamentos:

Requer um capital inicial significativo.

Requisitos de material:

Apenas alguns metais são adequados.

Escopo limitado:

Melhor para formas e tamanhos específicos.

MATERIALS FOR IMPACT Extrusion

A seleção do material é fundamental para o sucesso do processo de extrusão por impacto. A escolha do material afeta a facilidade de extrusão, a qualidade do produto final e a variedade de aplicações possíveis. Aqui, discutiremos os materiais comuns usados na extrusão de impacto, suas características e os graus ou ligas típicos.

Alumínio

Cobre

Chumbo

Zinco

Titânio

Alumínio

Cobre

Chumbo

Zinco

Titânio

Tratamento de superfície na extrusão por impacto

O tratamento de superfície é um aspecto vital do processo de extrusão por impacto, afetando significativamente o desempenho, a durabilidade e a aparência do produto final. O tratamento adequado da superfície pode melhorar propriedades como resistência ao desgaste, resistência à corrosão e estética. Aqui, exploraremos a importância do tratamento de superfície, os métodos comuns e seu impacto no desempenho do produto.

Importância do tratamento de superfície

O tratamento da superfície é fundamental por vários motivos:

Enhances Durability: Increases resistance to wear and tear, extending the product’s lifespan.
Improves Corrosion Resistance: Protects against environmental factors, preventing rust and degradation.
Optimizes Surface Properties: Improves hardness, reduces friction, and enhances conductivity.
Aesthetic Appeal: Provides a polished, uniform appearance, improving the product’s marketability.
Functional Performance: Enhances specific properties required for the product’s application, such as electrical conductivity or reflectivity.

Métodos comuns de tratamento de superfície

Polimento mecânico

Purpose: To smooth the surface and improve its appearance.
Process: Involves abrasive techniques to remove surface irregularities and achieve a mirror-like finish.
Applications: Used for products requiring a high-gloss finish, such as consumer goods and decorative items.

Tratamento químico

Purpose: To clean and prepare the surface for further processing.
Process: Involves using acids, alkalis, or other chemicals to remove oxides, scale, and contaminants.
Applications: Pre-treatment for plating or coating processes, ensuring better adhesion and uniformity.

Galvanoplastia

Purpose: To deposit a thin layer of metal onto the surface.
Process: Involves using an electrolytic solution to deposit metals such as chromium, nickel, or gold onto the product.
Applications: Used in electronics, automotive, and jewelry for enhanced corrosion resistance, electrical conductivity, and aesthetics.

Shot Peening

Purpose: To improve fatigue strength and resistance to stress-corrosion cracking.
Process: Involves bombarding the surface with small spherical media to induce compressive residual stresses.
Applications: Used in aerospace, automotive, and heavy machinery components to enhance durability.

Anodização

Purpose: To increase the thickness of the natural oxide layer on the surface.
Process: An electrochemical process that enhances corrosion resistance and allows for dyeing the surface in various colors.
Applications: Commonly used for aluminum products in the aerospace, automotive, and consumer electronics industries.

Revestimento em pó

Purpose: To apply a protective and decorative coating.
Process: Involves applying a dry powder to the surface and curing it under heat to form a durable finish.
Applications: Widely used in the automotive, appliance, and furniture industries for a high-quality, long-lasting finish.

Passivação

Purpose: To enhance corrosion resistance.
Process: Involves treating the surface with a nitric or citric acid solution to remove free iron and form a passive oxide layer.
Applications: Used for stainless steel and other corrosion-resistant alloys in medical and food processing equipment.

Surface Treatment Impact on Product Performance

Wear Resistance

Surface treatments like electroplating and anodizing can increase the wear resistance of products used in harsh environments, making them more resilient in such conditions as corrosion.

Corrosion Resistance

Corrosion-resistant treatments such as anodizing, passivation, and powder coating provide crucial corrosion protection to products subjected to extreme environments.

Aesthetics

Aesthetics Mechanical polishing, anodizing, and powder coating enhance the aesthetic value of products to make them more desirable to consumers.

Functional Properties

Electroplating with metals like gold or silver enhances electrical conductivity, essential for electronic components.

Anodizing can improve thermal conductivity and emissivity, beneficial for heat dissipation applications.

Choosing the appropriate surface treatment depends on several factors:

Material Type: Different materials respond differently to surface treatments. For example, aluminum is commonly anodized, while steel might be electroplated or powder coated.
Application Requirements: Consider the specific performance needs such as corrosion resistance, wear resistance, electrical conductivity, and aesthetic requirements.
Cost and Production Volume: Some surface treatments are more cost-effective for large production volumes, while others may be better suited for smaller, high-value items.
Environmental Considerations: Eco-friendly processes and materials are increasingly important in modern manufacturing.

Applications of Impact Extrusion

Impact extrusion is a versatile manufacturing process used across various industries due to its ability to produce high-quality, lightweight, and complex metal parts. Here, we explore the specific applications of impact extrusion in different sectors:

Automotive Industry

Aerospace Industry

Electronics Industry

Packaging Industry

Medical
and Pharma-ceutical Industry

Consumer Goods

Energy Industry

Automotive Industry
Aerospace Industry
Electronics Industry
Packaging Industry

Components:

Engine Parts: Cylinders, pistons, and valve lifters are often produced using impact extrusion due to the need for high strength and precise tolerances.
Heat Exchangers: The process is ideal for creating thin-walled tubes and fins used in radiators and intercoolers.
Brackets and Supports: Lightweight yet strong components that support various systems within the vehicle.

Benefits:

Weight Reduction
Strength and Durability
Precision

Components:

Structural Parts: Frames, ribs, and stiffeners used in aircraft fuselage and wings.
Landing Gear Components: Strong and lightweight parts that need to withstand high-impact forces.
Heat Shields and Panels: Thin-walled components used in thermal protection systems.

Benefits:

High Strength-to-Weight Ratio
Corrosion Resistance
Precision Manufacturing

Components:

Enclosures and Housings: Cases for electronic devices such as smartphones, laptops, and tablets.
Connectors and Contacts: Precision parts used in electrical connectors and interconnects.
Heat Sinks: Efficiently dissipate heat from electronic components.

Benefits:

Thermal Management
Miniaturization
Aesthetic and Functional Finishes

Components:

Metal Cans and Containers: Beverage cans, aerosol cans, and food containers.
Tubes: Collapsible tubes for products such as toothpaste, creams, and gels.

Benefits:

Seamless Construction
High-Speed Production
Recyclability

Medical and Pharmaceutical Industry
Consumer Goods
Energy Industry

Components:

Medical Devices: Housings and components for devices such as inhalers, insulin pens, and surgical instruments.
Implants: Structural components for orthopedic implants and dental implants.

Benefits:

Biocompatibility
Precision and Cleanliness
Customizability

Components:

Sporting Goods: Components for items like golf clubs, fishing reels, and bicycle frames.
Appliances: Structural and functional parts for household appliances.
Tools: Durable and lightweight hand tools and power tool components.

Benefits:

Enhanced Performance
Durability
Aesthetic Appeal

Components:

Battery Housings: Casings for lithium-ion and other batteries used in electric vehicles and portable electronics.
Heat Exchangers: Components for systems in power plants and renewable energy installations.
Fuel Cells: Parts used in hydrogen fuel cells and other energy generation devices.

Benefits: