Low Pressure Carburizing ALLCARB®

Carburizing or carburation is a thermochemical treatment aimed at hardening steels by adding carbon and increasing surface hardness. 

  • 450 x 450 x 600 mm – 1200 x 1200 x 1800 mm
  • 20 – 3000 kg
  • Graphite
  • GRAPHTIL® man-machine interface
  • 10-2 mbar, 10-5 mbar, 10-6 mbar
  • Max 1050°C, 1250°C, 1350°C, 1500°C
  • Cooling pressure: 0,9 bar, 1,2 bar, 5 bar, 12 bar abs
  • ALLCARB® low-pressure carburizing
  • ALLCARB® low-pressure carburizing
  • Carbonitriding
  • Steel quenching (without surface oxidation)


We would like to send you a personalized offer tailored to your requirements.

You can reach us by phone, comfortable via e-mail or through our contact form.

+33 (0)4 74 94 34 44


To request form

Detailed description

Carburizing is a thermochemical treatment aimed at hardening steels by adding carbon and increasing surface hardness. Low-pressure carburizing nowadays is an efficient alternative to conventional carburizsing / carburation techniques, notably bringing about noticeable improvements in homogeneity, penetration and a total absence of intergranular oxidation.

BMI optionally offers the ALLCARB® process for its entire range of high-temperature furnaces (vacuum annealing, vacuum gas quenching and vacuum oil quenching). This technique has been in operation since 1990 in sectors such as aeronautics and the automotive industry. The technique, the use of gas, carburizing and the systems are the subject of numerous patents.

The ALLCARB® technique is distinguished by its industrial results: precise, reproducible and homogeneous. Its use is facilitated by a software assistant, which helps to calculate the cycle parameters according to the depth sought and the steel grade. However, the user retains the possibility of modifying them in order to optimise them for his specific application.

Different from the current low-pressure carburizing techniques, ALLCARB® perfectly meets industrial constraints:

  • Large / dense load treatments
  • Deep penetration in cylinder bores
  • Reduced tolerance of carburised depth
  • Better control of surface carbon

The carburizing gases generally used at low-pressure were replaced by a gas that ensured perfect reproducibility with neither the inconveniences of propane, which does not penetrate thoroughly and forms soot, nor those of methane whose dissociation is difficult to control.

The ALLCARB® technique is handled automatically by a pilot software that determines the progress of the cycle to obtain the desired carbon profile. The choice of temperature is left to the user to optimise the balance between the carburising duration, deformation and dispersion. Atmosphere management is ensured by a vacuum gauge, a pumping unit and mass flow meters. On the basis of four parameters: temperature, steel grade, carburizing depth and surface carbon, the software establishes the pressures, time and outputs to be applied during the cycle.

As a standard, the ALLCARB® technique is planned for an injection-controlled single-sequence operation but can also be used in a multi-boost mode (series of enrichment phases).

The following furnaces can be equipped with ALLCARB® low-pressure carburizing: BMICROB8_TVSE8_TB5_THB6_TH, P16_THV6_TH and B5_T.