Poederlasermaterialen: Soorten, voordelen en nadelen

mei 16, 2022

As an advanced surface engineering and remanufacturing method, laserbekleding technology uses a high-energy laser beam to rapidly melt pre-deposited or synchronously delivered alloy powders, forming a metallurgically bonded cladding layer on the substrate surface. This significantly enhances the wear resistance, corrosion resistance, and high-temperature performance of the workpiece. In the entire laserbekleding process, the choice of powder material directly influences the cladding quality and application performance. This article systematically reviews the commonly used laserbekleding powder materials, including self-fluxing alloy powders, composite powders, ceramic powders, and other metal-based materials, analyzing their classification, properties, and applicable scenarios to provide a reference for material selection.

1. Self-Fluxing Alloy Powders

Self-fluxing alloy powders are the most extensively researched and widely applied materials in laserbekleding. They mainly include iron-based, nickel-based, and cobalt-based alloys. These powders contain elements like boron and silicon, which give them excellent deoxidation and slagging capabilities, effectively reducing oxidation and porosity in the cladding layer and improving process quality. In laserbekleding, these powders are highly adaptable to various substrates (such as carbon steel and stainless steel) and are widely used for the repair and enhancement of industrial components.

1.1 Iron-Based Self-Fluxing Alloy Powders

Iron-based powders are suitable for locally wear-resistant and easily deformable parts, typically made from cast iron or low-carbon steel. The main advantages are a wide raw material source, low cost, and good wear resistance. However, the drawbacks include a higher melting point and poorer oxidation resistance, leading to potential cracking and porosity during laserbekleding. In recent years, adding rare earth elements to iron-based powders has significantly improved their corrosion resistance and crack resistance, expanding their application potential in laserbekleding.

1.2 Nickel-Based Self-Fluxing Alloy Powders

Nickel-based powders are widely used in laserbekleding due to their excellent wettability, corrosion resistance, and high-temperature self-lubricating properties. In harsh conditions (such as severe impact or abrasive wear), hard particles like carbides and nitrides are often introduced into the nickel-based powder to form composite coatings, further enhancing their performance.

1.3 Cobalt-Based Self-Fluxing Alloy Powders

Cobalt-based powders are known for their excellent high-temperature resistance, corrosion resistance, and impact resistance, commonly used in high-end industrial fields like petrochemicals and power generation. During laserbekleding, cobalt-based materials rapidly form a reinforcing phase upon melting, and with the addition of alloy elements like nickel and chromium, they effectively suppress crack formation and improve the bond strength between the coating and substrate.

2. Composite Powders

Composite powders are typically made by mixing or coating metals (such as nickel or cobalt) with high-melting-point ceramic particles (such as carbides and oxides). These powders are used in laserbekleding to create ceramic-reinforced metal matrix composite coatings, combining the toughness of metals with the wear resistance and high-temperature properties of ceramics. For example, powders coated with tungsten carbide or chromium carbide can effectively prevent the degradation and decomposition of ceramic particles during the laser process, significantly enhancing the coating’s performance. This is one of the hottest research directions in laserbekleding technologie.

3. Ceramic Powders

Ceramic powders, mainly including oxides (such as aluminum oxide, zirconium oxide) and silicides, are used in laserbekleding for their excellent high-temperature stability, wear resistance, and corrosion resistance, often in thermal barrier coatings or protective layers in special conditions. However, ceramics and metal substrates have significant differences in thermal expansion coefficients and elastic moduli, leading to cracks and peeling after laserbekleding. Researchers have designed transition layers or added components like CaO and SiO₂ to alleviate these stresses, but this remains a major challenge in laserbekleding.

4. Other Metal-Based Cladding Materials

In addition to the categories above, special metal powders such as copper-based, titanium-based, aluminum-based, magnesium-based, and zirconium-based materials have also shown unique value in laserbekleding. For example:

Copper-Based Materials: Due to their good electrical conductivity and liquid phase separation properties, copper-based powders can be used to create self-reinforced composite coatings.

Titanium-Based Materials: Commonly used to improve biocompatibility or corrosion resistance, titanium-based composite powders used in laserbekleding can significantly enhance the wear resistance of medical titanium alloys.

Aluminum-Based and Magnesium-Based Materials: These are often used for surface modification of light alloys. Laserbekleding with aluminum-based powders can effectively improve the hardness and corrosion resistance of magnesium alloys.

Zirconium-Based Materials: Laserbekleding of zirconium-based powders on titanium alloys forms a high-hardness, non-crystalline reinforced layer, making them suitable for high-strength applications.

5. Summary and Application Outlook

The choice of materials in laserbekleding directly impacts the cladding layer’s performance and process success. Different powder systems vary significantly in terms of cost, performance, and process adaptability, requiring careful selection based on specific application needs. Currently, laserbekleding technology plays a crucial role in the remanufacturing of parts, surface strengthening, and high-end equipment repair. For example, the repair of key components like rollers, molds, and hydraulic columns can restore their performance to over 90% of the original parts’ specifications, with costs only about one-fifth of replacing them, significantly improving the equipment’s service life and operational economy.

However, laserbekleding materials are not yet systematized or standardized, and the composition design and performance prediction are still in the research phase. In the future, with the continuous development of materials and process optimization, laserbekleding technology is expected to replace traditional coating and overlay processes in more industrial applications, becoming a core technology in high-end manufacturing and green remanufacturing.

Graham Luo

Dr. Graham Luo - Senior Engineer, Titanium MIM Specialist Dr. Graham Luo is een erkende autoriteit op het gebied van Metal Injection Molding (MIM), met een gespecialiseerde focus op titaniumlegeringen. Momenteel is hij Senior Engineer bij een Nonferro Metals Research Institute. Hij heeft een Ph.D. van de Helmholtz Association of German Research Centres en heeft gewerkt als postdoctoraal onderzoeker, waardoor hij een grondige theoretische basis heeft en ervaring heeft opgedaan bij vooraanstaande Europese onderzoeksinstellingen. Zijn onderzoek richt zich op de kern van MIM-technologie en concentreert zich op kritieke gebieden zoals de reologie van titaniumgrondstoffen, katalytische/thermische ontslijpprocessen met een laag koolstof/zuurstofgehalte en de...

Lees meer artikelen van Graham Luo