Gear Laser Hardening Process and Its Advantages

Gears are widely used components in the mechanical manufacturing industry. To enhance the load-bearing capacity of gears, surface hardening treatment is required. However, traditional gear quenching processes, such as surface chemical treatments like carburizing and nitriding, induction surface hardening, and flame surface hardening, primarily suffer from two issues: significant deformation after heat treatment and difficulty in obtaining a uniformly distributed hardened layer along the tooth profile. This affects the service life of gears. Below, the process and advantages of laser quenching for gears are introduced.

Gear Laser Quenching Process:

1. Surface Pre-treatment Coating: To improve the absorption rate of laser by the metal surface, the material's surface must be treated before laser heat treatment. This involves applying a coating with high laser absorption capability on the metal surface where laser treatment is needed. Common surface pre-treatment methods include phosphating, surface roughness improvement, oxidation, spraying (brushing) paint, and coating, with spraying (brushing) paint being the most commonly used.

2. Axial Tooth-by-Tooth Scanning: Gear laser quenching axial tooth-by-tooth scanning is a method that uses a broadband laser beam to perform laser quenching on gears. The broadband laser beam scanning typically employs multiple beams to form a wide band. The laser beam moves along the axial direction of the gear for scanning, covering one tooth surface at a time. After the indexing motion rotates by one tooth pitch, the laser beam scans another tooth surface, proceeding tooth by tooth until all tooth surfaces of the entire gear are scanned.

Advantages of Gear Laser Quenching:

1. Special Advantage: After laser quenching, the gear tooth surface becomes hard while the root remains soft.

2. High Wear Resistance: Gears treated with laser quenching exhibit high hardness and fine metallurgical structure, offering better wear resistance compared to traditional quenching processes. Laser quenching induces compressive stress in the structure, enhancing the gear's fatigue resistance.

3. Minimal Deformation: Laser quenching results in tooth profile deformation of less than 0.01mm, with no cracks, and maintains the original surface roughness. Gears after laser quenching can be directly installed and used.

4. Short Production Cycle: Due to minimal deformation from laser quenching, gears generally do not require regrinding, simplifying the production process, improving production efficiency, and reducing production costs.

5. Expanded Material Selection for Gears: Lower-cost steel grades can be used to manufacture gears, with laser quenching applied to enhance tooth surface hardness, ensuring performance requirements are met.

For 8 years since its establishment, Guosheng Laser has focused on R&D technology and production. The company has established Xi'an Aerospace R&D Design Center and Weinan Production Base. Guosheng Laser is a high-tech enterprise specializing in the R&D, manufacturing, and sales of automated laser cladding equipment, high-speed laser cladding equipment, laser quenching equipment, laser welding equipment, and 3D printing equipment. It provides customers with comprehensive solutions for structurally and functionally integrated laser additive manufacturing technology. Guosheng Laser always emphasizes innovation and R&D, with an engineering team covering project R&D, design, development, testing, analysis, and pre-sales and after-sales services for laser cladding equipment and other projects. Leveraging extensive technical resources, strong R&D capabilities, advanced production technology, fast delivery cycles, and flexible technical services, the company offers high-cost-effective products and services to customers.

Laser quenching technology enables low-grade materials to achieve high-performance surface modification, combining low-cost part manufacturing with high-performance working surfaces, and resolving the contradiction between overall strengthening and other surface strengthening methods that are difficult to overcome. It has had a significant beneficial impact on the selection, matching, design, and manufacturing of materials and performance for critical components, also creating considerable economic and social benefits. It is no exaggeration to say that laser heat treatment can address almost all issues related to metal surface heat treatment, but its processes require continuous exploration, discussion, and validation.