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Sol-based coatings derived from organically modified silanes and metal alkoxides have been investigated for the past two decades for their applicability as barrier coatings for corrosion protection of stainless steels and mild steels. Colored sol-gel coatings can also be generated by the addition of pigments. Recently, lot of attention has been given to use of radiation (UV or NIR) curing for densification of protective coatings on metals/steels. In this context, investigations were carried out on the mechanical and corrosion protection properties of UV-curable transparent and colored sol-gel coatings on mild steels for comparison with a painted substrate.

One of the most popular weight reduction strategies in auto bodies is usage of tailor welded blanks (TWB). TWBs with high-strength low-alloy steels and advanced high-strength steels (AHSS) offer possibility of significant weight reduction. In the present work laser welding studies were carried out to fabricate TWB's involving 1.6 mm thickness AHSS DP 590 (dual phase steel) and 0.8 mm thickness conventional IF (interstitial free) steel in different combinations and characterized for their metallurgical and formability characteristics. Fusion zone microhardness was varying with change in material combination. While DP590-DP590 and IF-IF have shown fusion hardness of 300-350HV and 150-180HV, respectively, the dissimilar DP590-IF showed a fusion zone hardness of 250-330HV.Beam offsetting towards the thinner side has reduced the peak hardness. Microstructural analysis revealed mixture of martensite and refined ferrite in the fusion zone of dissimilar welds.