Mathemathical Equations of the Influence of Molybdenum and Nitrogen in Welds

The paper offers mathematical equations of the influence of micro-jet cooling on structure and impact toughness properties of metal weld deposit. Weld metal deposit (WMD) was carried out for standard MIG welding and for MIG welding with micro-jet cooling. This new method is very promising mainly due to the high amount of AF (acicular ferrite) and low amount of MAC (selftempered martensite, retained austenite, carbide) phases in WMD. That structure corresponds with very good mechanical properties ie. good impact toughness of welds at low temperature. Micro-jet cooling after welding can find serious application in automotive industry very soon. Until that moment only argon, helium, nitrogen and gas mixtures of argon were tested for micro-jet cooling after welding. The best results of mechanical properties of WMD in presented welding method correspond with micro-jet argon cooling.