Quenched and tempered steels are unalloyed and low-alloyed stainless steels with a carbon content of 0.2% to 0.6%. Alloyed grades also contain chromium, nickel and molybdenum. Quenched and tempered steels from BGH are characterised by an excellent combination of strength and toughness. Due to the high hardness and strength of these steels, coupled with their good ductility, heat-treatable steels are particularly suitable for highly stressed applications in machine and gear construction.
Two-stage heat treatment
The tempering of the steels takes place in a two-stage heat treatment process. In the first step, austenitising, the steel is heated conventionally or inductively to approx. 900 °C and then rapidly cooled in a water, oil or polymer bath. In the second step, the material is tempered to achieve the required mechanical properties – tempering temperatures of 500–700 °C are common. Hardening and tempering produce a fine and homogeneous microstructure.
Water quenching of steel bars
BGH's heat-treatable steels impress with their high tensile strength and fatigue strength combined with consistent toughness. This combination of properties makes them particularly suitable for applications such as pinion and camshafts, spindles, gear wheels, other gearbox and engine parts, tools, connecting and fastening elements and safety bolts.
BGH's heat-treatable steels are manufactured in our modern heat treatment facilities using conventional or inductive heating. This, combined with the expertise of our employees, guarantees compliance with narrow process windows and precise temperature control to achieve the required mechanical and technological properties.
Special single-bar heat treatment for the most demanding requirements
Inductive single-bar heat ttreatment is a special quenching and tempering process in which each individual bar is treated separately. This enables highly precise control of the heat treatment and thus of the properties of each bar. The bars heat-treated inductively at BGH are characterised by optimum homogeneity in terms of mechanical properties – both within a single bar and within the entire heat treatment batch. In addition, they are free of residual stresses – essential for high-precision and fail-safe components.
Inductive single-bar heat treatment
Wide range of applications for BGH heat-treated steels
Due to their high strength and toughness, heat-treatable steels are used in a wide range of demanding technical applications, such as in the roller bearing, transport and manufacturing industries. Thanks to their adaptable mechanical properties, BGH heat-treatable steels provide a reliable basis for robust designs in numerous industrial sectors.
Special screws, nuts and fasteners
Screws and other high-load fasteners require materials that offer high strength, toughness and hardenability, as well as reliable performance under dynamic loads.
Alloyed heat-treatable steels such as material 40NiCrMo8-4 / B23 / 1.6562, which is specially designed for extreme conditions, have proven particularly effective here.
40NiCrMo8-4 / B23 / 1.6562 in accordance with ASTM A320 is primarily used in fasteners for low-temperature applications. These are special screws, bolts and nuts that hold critical components such as pressure vessels, valves and fittings securely together in the oil and gas industry, petrochemicals and energy production, even at low temperatures.
In addition, heat-treatable steel 42CrMo4 (1.7225) offers an outstanding combination of high strength, very good hardenability and excellent wear resistance. This also makes it a versatile option for demanding screws and fasteners in mechanical engineering and vehicle construction – wherever robust components have to provide permanently reliable power transmission.
All materials for fasteners are manufactured in accordance with strict industry standards – including ASTM, API, ANSI, DIN, ISO or RCC‑M – or according to customer-specific specifications to ensure maximum safety and quality.
Special screws made of material 1.6562 / 40NiCrMo8-4/ B23
Guide columns/tie rods for press construction
In press construction, maximum strength, toughness and long-term dimensional stability are among the key factors – particularly in the case of guide columns, tie rods and heavily loaded frame components.
Materials such as 1.6580, 1.6582 and 1.7225 provide the ideal basis for this and ensure reliable performance even under extreme forces and cyclic loading.
Quenched and tempered steel 30CrNiMo8 (1.6580) impresses with its high strength, excellent toughness and outstanding hardenability, making it particularly well suited for large cross-sections of components subject to heavy loads.
The lower-alloyed 34CrNiMo6 (1.6582) is used as an alternative for components subjected to high dynamic loads where slightly lower strength is required. 42CrMo4 (1.7225) grade is a robust and cost-effective alternative for standard applications.
Thanks to their high tensile strength and fatigue strength, as well as their excellent wear resistance, all these materials are ideal for power transmission components, tension and compression systems, and load-bearing structural components that require both hardenability and toughness.
Together, these materials form a range that is ideally suited to the demands of modern presses – from high-pressure guide columns to tie rods in continuous operation. Their load-bearing capacity, resistance to deformation and long-term stability make them the first choice for high-performance and safe designs in demanding plant engineering.
Forged and finished columns made from 30CrNiMo8 (1.6580)
Deep hole forged high- and ultra-high-pressure tubes
LDPE production involves unique conditions: extreme pressures, high temperatures, prolonged cyclic loading and the most demanding requirements in terms of material stability. It is precisely here that the high-alloy quenched and tempered steels 30CrNiMo8 and 24NiCrMoV14‑6 demonstrate their exceptional performance.
30CrNiMo8 (1.6580) combines very high strength, excellent toughness and outstanding hardenability, which means that the material retains a uniform, resilient structure even in large wall thicknesses. It is therefore particularly suitable for components with high dynamic loads, such as those used in polymer chemical plant engineering.
The specially alloyed 24NiCrMoV14-6 (1.6952) was developed for pressure systems subjected to extremely high stresses. Its Ni-Cr-Mo-V alloy not only ensures exceptional strength and toughness, but also makes the material resistant to temperature embrittlement and suitable for use across a wide temperature range of approx. –40 °C to +300 °C.
With these properties, 30CrNiMo and 24NiCrMoV14- are among the most efficient material options for LDPE processing, where reliability, material reserves and safety are top priorities. Their combination of strength, heat resistance and structural stability enables highly safe operation even under the most extreme process conditions.
Deep hole forged tubes from BGH made from 24NiCrMoV14-6 (1.6952) ensure safety and process stability in LDPE production
Gearboxes and gear modules
In modern turbo transmissions, every micrometre counts: extreme speeds, the highest power densities and maximum efficiency require materials that perfectly combine strength, wear resistance and thermal stability. This is precisely where quenched and tempered steels such as 1.6580, 1.6582, 1.7225 and 1.7227 really come into their own.
The high-strength quenched and tempered steel 1.6580 (30CrNiMo8) offers exceptional toughness, high strength and excellent hardenability, even in large cross-sections. This makes it ideal for heavily loaded gear components, such as those used in turbine, generator and heavy machinery engineering.
As a standard material for slightly lower requirements in terms of strength and hardening depth, 1.7225 (42CrMo4) impresses with its high toughness, excellent strength, very good hardenability and wear resistance – decisive criteria for gear stages, shafts and power transmission components in high-performance gearboxes that have to transmit the highest torques on a permanent basis. The “material family” comprising 1.7218, 1.7220, 1.7225 and 1.7228 also offers materials optimally tailored to the respective application, thereby complementing the portfolio.
BGH Edelstahl’s materials deliver maximum efficiency and reliability in demanding industries such as power generation, petrochemicals, shipping, renewable energy and modern manufacturing.
Gear modules made from 34CrNiMo6 (1.6582) BGH stainless steel ensure reliable power transmission in gearboxes.
Safety bolts and barrels for defence technology
When it comes to maximum operational reliability under extreme conditions, the heat-treated steel 35NiCrMoV12-5 (1.6959) sets the standard:
In crane construction, it has proven itself as a safety bolt – precisely where high loads, vibrations and changing temperatures demand uncompromising reliability.
At the same time, 35NiCrMoV12-5 is established in defence technology as barrel steel for heavy artillery. The material performance standard confirms its suitability for high-pressure pipe systems with strictly defined chemical and mechanical properties – synonymous with long-term stability and precision in the most demanding applications.
35NiCrMoV12‑5 has high strength, excellent toughness and good wear resistance. Its nitridability allows hard, fatigue-resistant surface layers to be achieved. The material remains tough and reliable even at extremely low temperatures..
Bolts made from 35CrNiMoV12-5 (1.6959) guarantee the safe operation of cranes worldwide.
Request QT steels from BGH Edelstahl
Due to its high tensile strength and fatigue strength, excellent wear resistance and toughness, QT steel is suitable for dynamically stressed parts in mechanical engineering, toolmaking, the automotive industry and other sectors. At BGH, you can obtain QT steels that meet your requirements for specific mechanical and technological properties.
Please contact us or check the stock availability of our standard grades.
In addtition to QT steels, we also offer stainless steels, tool steels as well as Ni-based alloys and special alloys" .
We look forward to working with you.