Cast iron is widely used in various industries due to its unique properties. However, the challenges of repairing these components can be daunting because of the welding process. Titanova, a leader in laser cladding, has developed a proprietary technique that enables the repair of the biggest castings.
This article will explore the benefits of cast iron, the challenges involved in repairing it, and how Titanova’s laser cladding technique addresses these issues.
Cast Iron: A Versatile Material
Cast iron is an iron-carbon alloy with a high carbon content of over 2% and silicon between 1-3%. This chemistry allows for lower melting points, which is a main benefit to the industry.
Cast iron has many classes and subclasses, each with unique properties and applications. The following are the several types of cast iron:
- Grey cast iron: used in gearbox cases, engine cylinder blocks, flywheels, and machine-tool bases
- White cast iron: used in anti-erosion piping and bearing surfaces
- Malleable iron: used in axle-bearing retainers, track wheels, and automotive crankshafts
- Ductile or nodular iron: used in gears, camshafts, and crankshafts
- Ni-hard Type 2: used in high-strength applications
- Ni-resist Type: used for resistance to heat and corrosion
Challenges of Repairing Cast Iron
Here are some of the main obstacles to repairing cast iron components:
Cast iron contains a high amount of carbon, typically between 2% and 4%. This carbon content causes the material to become brittle and prone to cracking when exposed to high heat during welding. Welding also causes the carbon to migrate to the weld pool, leading to porosity and weakening the weld joint.
Microscopic Impurities and Inclusions
Cast iron is not a pore-free material; it contains microscopic impurities and inclusions that make it challenging to repair. These inclusions come in various shapes — from flakes to spherical nodules — and can cause stress concentration, leading to cracks and fractures.
Saturation of Lubricants and Other Surface Substances
Cast iron components used in industrial applications are often exposed to various substances. This includes lubricants, greases, and water that can saturate the surface and create a barrier to adhesion during the repair process. This makes it difficult to achieve proper bonding and leads to failure in the repaired area.
Costly and Time-Consuming Preheat Requirements
Repairing cast iron often requires preheating the component to slow down the cooling rate of the weld and the surrounding area. However, preheating large cast iron components can be time-consuming and expensive, often requiring temperatures between 500-1200 °F. Preheating must also be done uniformly, or it can cause the part to crack, making the repair process even more challenging.
Titanova’s Solution: Advanced Proprietary Laser Cladding Solutions
Titanova has years of experience and expertise in laser cladding techniques! This has allowed us to develop proprietary methods specifically designed for repairing all types of cast iron components.
Our laser cladding technique uses a laser beam to melt a powder or wire-based coating material. Afterward, it is bonded onto the surface of the cast iron component. This process results in a metallurgically bonded layer highly resistant to wear and corrosion.
Laser cladding offers several benefits over traditional welding techniques for repairing cast iron components. Unlike conventional welding, laser cladding requires minimal preheat, significantly reducing the time and cost associated with repairs. Additionally, the laser cladding process produces a much smaller heat-affected zone, reducing the risk of cracking during the repair process.
Trust Titanova to provide the laser cladding expertise to keep your operations running smoothly!
Contact us today to learn more about our services and how we can help you achieve your material processing goals.