HOT WORK TOOL STEELS
Hot work steels are designed to operate at high temperatures. Their chemical and physical properties are not found in carbon and standard structural steels.
Desired Material Properties:
- Hot wear resistance
- Erosion resistance
- Oxidation resistance
- Thermal fatigue resistance
- Thermal shock resistance
- Temper resistance
- Softness and toughness
- Excellent machinability
Quality List & Catalogs
- General Properties
- BEYLOS Family
- Production Process
- Heat Treatment
- Comparison
- Documents
Hot work steels are designed to operate at high temperatures. Their chemical and physical properties are not found in carbon and structural steels. These superior properties are obtained after a balanced chemical analysis and controlled production process.
Advanced heat treatments such as oxidation processes are applied to increase surface resistance at operating temperatures and hot tearing strength, preventing parts from losing their properties in a short time.
Hot work steels must definitely be resistant to tempering and thermal degradation. In addition, at high operating temperatures, the grain size of the material must be minimally affected. Thermal conductivity and friction coefficient are vital for thermal cracking. In this respect, thermal conductivity should be as high as possible, and friction should be extremely low.
Our hot work steels are subjected to heat treatment after machining. Since they are delivered in soft annealed condition, their machinability is extremely good. Delivery hardness is lower than 250 HB. An ideal hot work tool steel must possess all these performance criteria at the highest level.
Lucchini RS tool steels are developed and designed to offer the most ideal material performance worldwide.
With a modern process, Lucchini RS has produced a hot work steel family containing Chromium, Molybdenum and Vanadium for the highest requirements and most complex applications. The most prominent and important characteristic feature of these steels is their ability to maintain their hardness and toughness even when exposed to high temperatures for long periods.
This superior property is achieved by the extremely balanced presence of three basic carbides in the structure. These carbides are Mo6C, VC and Cr7C3. This carbide composition provides high hardness and they tend to agglomerate with each other under controlled diffusion of alloying elements.
These steels are offered under two main brands depending on the production process applied:
- BeyLos® Series: Produced with high purity via VD (Vacuum Degassed) technology.
- EskyLos® Series: Re-melted using ESR (Electro-Slag-Remelting) technology in addition to VD technology to reach ultra-purity levels.
BeyLos® 2343 and BeyLos® 2344 grades offer excellent solutions for very different applications in hot forming and extrusion fields thanks to precise balancing of Vanadium amounts.
Our hot work steels are produced with highly specific and modern manufacturing methods. All grades in the BeyLos® family are produced with a special technology called "Super Clean", which minimizes the inclusion rate in steel.
Thanks to the Vacuum Degassing (VD) process, gases such as hydrogen, nitrogen and oxygen that negatively affect the mechanical performance of steel are completely removed from the structure. Thus, gas cavities and inclusion risks are eliminated.
Advantages Provided by the ESR (Electro-Slag Remelting) Method:
- Extraordinary increase in toughness and fatigue resistance of the material,
- High-level non-metallic cleanliness,
- Fully homogeneous (isotropic) mechanical properties of the steel in all directions,
- Keeping the dendritic segregation amount at the lowest level.
Liquid metal melted by the ESR method passes through the slag layer and is purified from inclusions with the help of a filter. Since the solidification process takes place rapidly, a homogeneous, purified and highly isotropic excellent microstructure is obtained.
To obtain maximum efficiency from hot work tool steels, heat treatment steps must be performed carefully in accordance with the manufacturer's instructions. After the austenitizing process, tempering should be applied at least twice, and a third tempering (stress relieving) is recommended to increase toughness.
Austenitizing (Hardening):
It is recommended to reach the austenitizing temperature with three-stage gradual preheating:
- 400°C: In the first preheating stage, internal stresses remaining from manufacturing are eliminated.
- 600°C ve 800°C: In the second and third preheating stages, the temperature difference between the outside and center of the part is balanced.
It is recommended to keep the heating rate at 150°C/hour. Soaking times should be calculated precisely according to the part thickness using the formula t = (x+39)/2 (t: soaking time, x: wall thickness).
Tempering:
For the first tempering temperature, 580°C is recommended for secondary hardening to occur. The second tempering temperature should be chosen slightly higher than the first temperature in accordance with the target working hardness. Tempering between 400°C and 550°C should be avoided as it is the embrittlement range that reduces toughness.
The grades of our steels are optimized specifically in line with industrial expectations:
- BeyLos® 2343 (H11): Excellent for die casting and hot forging applications with high cracking risk, where toughness and thermal shock resistance are primarily at the forefront.
- BeyLos® 2344 (H13): Contains higher Vanadium compared to 2343. Has higher hot wear and temperature resistance, ideal for extrusion dies and hot shear blades.
- BeyLos® 2365 (H10): %3 Chromium, Molybdenum and Vanadium combination offers high thermal conductivity. Preferred in heavy forging presses and die cores under high operating temperatures.
- BeyLos® 2367: Offers excellent mechanical strength at high temperatures thanks to its Molybdenum content, while maintaining the superior toughness characteristic of 2343.