Heat treatment with laser hardening
Nextema srl was founded in 2015 as a spin-off of the Laser Group of the Department of Industrial Engineering of the University of Bologna. The laser hardening heat treatment experience we have gained in these years of activity allows us to meet the highest expectations of manufacturers of:
Flat and globoidal cams
Made from alloy quenched and tempered steels (e.g., 42CrMo4, 39NiCrMo3), Unalloyed quenched and tempered steels (e.g., C45, C48), Mold steels (e.g., W1.2312-40CrMnMoS8-6), Tool steels (e.g., X210Cr12), Cast irons (e.g., GJS700-2, GJS500-7)
Laser hardening activities
We have a robotic island, with which we perform contracts of surface heat treatment and direct deposition. In both cases we offer this service for different types of components and batch sizes.
We provide stand-alone plants, which enable mechanical components with even very complex geometries and different weights and dimensions to be machined by means of innovative laser technologies. Furthermore, the process works without the need for repositioning, thus accommodating the production needs of the manufacturing industries.
Advantages of laser hardening heat treatment
- The laser process has high precision, and absolute, certified repeatability.
- The hardness generated is the maximum possible for the material of choice
- Effective depths can range from 0.2 to 0.5 mm. Hardening depths of less than 1 mm result in very small distorions that do not require subsequent treatments.
- The systems do not require tempering fluids and do not emit fumes
- The energy costs of laser hardening can be, per units of components treated, up to 100 times lower than those required by case hardening and induction hardening
Other types of processing
Nextema supports companies with technological innovation to improve and design new products and processes, to meet the needs of an increasingly dynamic and competitive market.
Our strength is the high specialization in the use of laser technology. The versatility of applications of the laser system allows our company to offer a wide range of processing possibilities, such as laser hardening, cladding, welding for lithium batteries and electric motors.
Laser hardening is a thermal treatment process used to improve the strength and durability of the components’ surfaces. A high powered laser diode is used in order to apply a significant amount of energy in very specific and precise areas of the surface. When the laser is working it heats instantly the material above the austenitizing temperature. Subsequently he metal cools down rapidly, forming a martenisitic structure. Compared to the other traditional hardening methods, laser hardening offers some advantages such as a minor risk of demormations, high precision and accuracy and a wide choice of suitable materials.
HOW TO PERFORM LASER HARDENING
The main steps of the process are:
Positioning of the piece under the diode laser. The laser hardening process is suitable to almost any kind of steel and cast iron which contains carbon.
Laser activation. Once the piece is in the correct position, the software activates the laser, which heats a localized surface just below its melting point. Triggered by the heat, the grid of carbon atoms rearrange itself.
Movement of the laser through the component’s surface. The area under the laser beam instantly reaches the target temperature. The sofware is programmed to move the laser across the surface of the component, following a prefixed path. The depth of the hardening is defined by the energy of the laser per unit area. After the has moved across an area, the surface rapidly cools by conduction. This process prevents the carbon atoms from reverting to their previous reticle, furthermore it causes the creation of a crystal structure known as martensite.