Laser cladding a surface treatment process that grants superior characteristics such as toughness, hardness, and corrosion resistance to the surface, and rebuilds cracked molds; as such, it can be a strong tool to prolong service life of mold steel. Furthermore, compared with the other similar coating processes – thermal spray, etc., laser cladding provides superior bonding strength and precision coating on a local area. In this study, surface characteristics are studied after laser cladding of low carbon steel using 18%Cr-2.5%Ni-Fe powder (Rockit404), known for its high hardness and excellent corrosion resistance. A diode laser with wavelength of 900-1070 nm is adopted as laser source under argon atmosphere; electrical power for the laser cladding process is 5, 6, and 10 kW. Fundamental surface characteristics such as crossectional microstructure and hardness profile are observed and measured, and special evaluation, such as a soldering test with molten ALDC12 alloy, is conducted to investigate the corrosion resistance characteristics. As a result of the die-soldering test by immersion of low carbon alloy steel in ALDC12 molten metal, the clad layer's soldering thickness decreases.

Abstract
1. Introduction
2. Experimental Procedure
3. Results and Discussion
    3.1. Macroscopic morphology
    3.2. Microscopic morphology
    3.3. Micro-hardness distribution of the cladding layer
    3.4. Soldering test
4. Conclusion
References

• Cheol-Woo Kim(Korea Institute of Industrial Technology) Corresponding author
• Hyo-Sang Yoo(Korea Institute of Industrial Technology)
• Kyun-Taek Cho(Korea Institute of Industrial Technology)
• Jae-Yeol Jeon(Korea Institute of Industrial Technology)
• Se-Weon Choi(Korea Institute of Industrial Technology)
• Young-Chan Kim(Korea Institute of Industrial Technology)