The Full Form of OHNS is Oil Hardened Nickel(Non – Srinking) Steel.

The Oil Hardening Non Shrinking (OHNS) die steel refers to a variety of carbon and alloy steels that are particularly well-suited for making tools. Though these steels are weldable, there is risk of crack formation. But, this can be avoided with convinced specifications like pre heating, proper choice of electrode etc., In the present work, OHNS die steel is welded with three different electrodes. The chosen electrodes were mild steel electrode, E312-16 chromium based electrode and E-NiCrFe-3 nickel based electrode. The OHNS steel is welded with these three electrodes and the welded specimens were examined for hot cracking tendency and mechanical properties of the joint. The hot cracking tendency was assessed by Houldcroft’s weldability test (Fishbone test). All the three electrodes proved the good results in terms of hot crack resistance and the specimen welded with E312-16 chromium based electrode provides good mechanical properties.