Journal of Applied Metalworking

, Volume 3, Issue 2, pp 110–119 | Cite as

The effect of nitrogen on the machinability of low-carbon, free-machining steels

  • J. D. Watson
  • R. H. Davies


Long turning tests on nitrogenized and non-nitrogenized 1214 and plunge forming tests on a range of AISI 12L14 steels with varying nitrogen contents have been carried out. Both tests have revealed an adverse effect of nitrogen on high-speed steel tool life in machining, and this is attributed to static strain aging of the cold-drawn feed stock prior to testing. No compensating beneficial effect of nitrogen on surface roughness was observed in the plunge forming tests, so it is concluded that, overall, nitrogen has a detrimental effect on machinability.

Regression analysis revealed that, after nitrogen, manganese sulfide size and shape had the next most significant effect on machinability of the commercially produced 12L14, all other compositional factors being essentially constant.


Nitrogen Content Tool Life Flank Wear Manganese Sulfide Apply Metalworking 
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Copyright information

© American Society for Metals 1984

Authors and Affiliations

  • J. D. Watson
    • 1
  • R. H. Davies
    • 1
  1. 1.Melbourne Research LaboratoriesThe Broken Hill Proprietary Co. Ltd.ClaytonAustralia

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