Aller au contenu principal

Cold heading

Screws, bolts, rivets, etc. are produced by cold heading: a process of high productivity using punch and dies to transform a steel wire rod at room temperature. A specific quenching and tempering process regularly follows cold heading in order to reach the final mechanical properties.

Ductility and strength required for cold heading are obtained by a wide range of low carbon, alloyed and boron grades produced according to international standards. Bainitic grades are also used in specific applications.

The steel grade is accordingly alloyed with elements such as manganese, chromium, boron and molybdenum depending on the final class targeted (8.8, 9.8, 10.9, 12.9). The chemical analysis is a trade-off between the necessary ductility prior to processing and the final properties obtained after quenching and tempering.

Specific grades have been developed for engine bolts with an ultimate tensile strength of over 1500 MPa and improved hydrogen resistance for a range from M6 to M14. The ultimate tensile strength of such grades can be adjusted in the range of 1200 - 1500 MPa with the adjustment of the tempering process to meet the requirements of 12.9 class bolts.

Key properties

Cold ductility and final mechanical properties
Microstructure homogeneity
Surface quality

20MnB5 screw: hardness profile, thermal simulation

NameMaterial No.
C4C1.0303XXX    0.02-0.06max. 0.100.25-0.40max. 0.02max. 0.025---0.02-0.06--
C8C1.0213XXX    0.06-0.10max. 0.100.25-0.45max. 0.02max. 0.025---0.02-0.06--
C10C1.1214XXX    0.08-0.12max. 0.100.30-0.50max. 0.025max. 0.025---min. 0.02--
C15C1.1234XXX    0.13-0.17max. 0.100.35-0.60max. 0.025max. 0.025---min. 0.02--
C20C1.0411XXX    0.18-0.22max. 0.100.70-0.50max. 0.025max. 0.025---0.02-0.06--
C221.0402XXX    0.20-0.24max. 0.150.40-0.60max. 0.015max. 0.015------
6MnB6    X   0.06-0.100.05-0.401.30-1.60max. 0.025max. 0.025max. 0.30----100-200
17MnB41.5520   X   0.15-0.20max. 0.300.90-1.20max. 0.025max. 0.025max. 0.30----8-50
20MnB41.5525   XXX 0.18-0.23max. 0.300.90-1.20max. 0.025max. 0.025max. 0.30----8-50
23MnB41.5535   XXX 0.20-0.25max. 0.300.90-1.20max. 0.025max. 0.025max. 0.30----8-50
28B21.5510   XXX 0.25-0.30max. 0.300.60-0.90max. 0.025max. 0.025max. 0.30----8-50
30MnB41.5526   XXX 0.27-0.32max. 0.300.80-1.10max. 0.025max. 0.025max. 0.30----8-50
32CrB41.7076      X0.30-0.34max. 0.300.60-0.90max. 0.025max. 0.0250.90-1.20----8-50
38B21.5515      X0.35-0.40max. 0.300.60-0.90max. 0.025max. 0.025max. 0.30----8-50
36CrB41.7077      X0.34-0.38max. 0.300.70-1.00max. 0.025max. 0.0250.90-1.20----8-50
30CrMoB1       X0.28-0.32max. 0.300.80-1.10max. 0.015max. 0.0150.15-0.30-0.08-0.150.02-0.06-8-50
27MnSiVS61.5232       0.25-0.300.15-0.801.20-1.600.0250.025----0.08-0.20-
34CrMo41.7220      X0.30-0.37max. 0.300.60-0.90max. 0.025max. 0.0250.90-1.20-0.15-0.30---
34CrNiMo61.6582      X0.30-0.38max. 0.300.50-0.80max. 0.025max. 0.0251.30-1.700.90-1.200.15-0.30---
41CrS41.7039      X0.38-0.45max. 0.300.60-0.90max. 0.025max. 0.0250.90-1.20-----

ArcelorMittal at NEMU 2019

ArcelorMittal Europe – Long Products' Business Division Bars & Rods will participate to NEMU, the International Conference dedicated to bulk metal forming, taking place on 14 and 15 May in Stuttgart, Germany. 


Latest news

17 juin 2024

ArcelorMittal introduces latest developments at Wire and Tube fair

Low carbon-emissions steel on the way: XCarb® recycled and renewably produced steel, made with a hig...
Find out more
16 avril 2024

Museum of the History of Polish Jews reinforced with ArcelorMittal rebars

Located in the former heart of Jewish Warsaw, the new Museum of the History of Polish Jews is a mode...
Find out more
1 avril 2024

Get your shopping list ready for the 64,000 m² shopping centre in Warsaw

Galeria Północna, a modern and functional new shopping centre has opened its doors in Warsaw (Poland...
Find out more
1 avril 2024

Krybar® in the Al-Zour LNG project in Kuwait

As from 2020, Kuwait will have a new liquefied natural gas (LNG) terminal, located near Kuwait City ...
Find out more
1 avril 2024

ArcelorMittal helps Warsaw grow

To contribute to the expansion of Warsaw underground, ArcelorMittal Europe – Long Products supplied ...
Find out more
29 mars 2024

LISI AUTOMOTIVE and ArcelorMittal join forces to help transform the automotive industry with XCarb® recycled and renewably produced low carbon-emissions steel

Committing to achieve carbon neutrality by 2050 and reducing CO2 emissions by 35% by 2030 in Europe,...
Find out more