Cooling Rate Control on Cold Cracking in Welded Thick HSLA Steel Plate

Abstract:

Cold cracking phenomenon is a very significant problem on welding of steel. This phenomenon usually occurs after welding process finishes in more than 24 hours. Crack often takes place in the heat affected zone area. Generally, cold cracking is due to hydrogen diffusion during welding process, residual stress and susceptible microstructure at low temperature (below 150°C). Welding process on thick plate high strength low alloy (HSLA) steel gives a high risk to cold cracking phenomenon. The cooling rate of thick plate during welding may increase the absorbtion of heat compared to thin plate. Controlling cooling rate is the main factor on welding of thick HSLA steel plate. A single v-butt joint on HSLA and S45C by using Gas Metal Arc Welding (GMAW) has been investigated. This investigation was carried out on a 40 mm thick HSLA steel by controlling cooling rate and by using cooling media such as air, blanket and electric heater. The result shows that prevention of cold cracking can be made by controlling cooling time at low temperature (T₃₀₀ - T₁₀₀) in order to keep the cooling time larger than the critical cooling time. The use of cooling media with electric heater can prevent the cold cracking at HSLA weldment. Crack can be found on the weldment due to the presence of stress concentration, local variation of hardness and microstructure, which may result in brittle fracture of the crack surface.

• Periodical: Materials Science Forum (Volume 689)
• Pages: 269-275
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.689.269
• Online since: June 2011
• Authors: Winarto Winarto, Muhammad Anis, Taufiqullah Taufiqullah
• Keywords: Cold Cracking, Cooling Rate, Fractography, Hardness, High Strength Low Alloy Steel, Microstructure

References

[1] J. Adamczyk, Development of the microalloyed constructional steels, Journal of Achievements in Materials and Manufacturing Engineering 14, (2006), pp.9-20.

[2] J. Cwiek, Hydrogen degradation of high strength weldable steels, Journal of Achievements in Materials and Manufacturing Engineering 20 (2007) pp.223-226.

[3] B. Swieczko-Zurek, S. Sobieszczyk, J. Cwiek, A. Zielinski, Evaluation of susceptibility of high-strength steels to hydrogen delayed cracking, Journal of Achievements in Materials and Manufacturing Engineering 18 (2006), pp.243-246.

[4] Kenneth Easterling, Introduction to the Physical Metallurgy of Welding, 2nd Edition, Butterworth Heinemann Limited (1992).

[5] N. Bailey, F.R. Coe, T.G. Gooch, P.H. M Hart, N. Jenkins, R.J. Pargeter, Welding Steels Without Hydrogen Cracking, 2nd Ed., Abington Publishing, England (1993).

DOI: 10.1533/9780857093097

[6] Y. Ito and K. Bessyo: A Prediction of Welding Procedure to Avoid Heat Affected Zone Cracking, IIW Doc. No. 1X-631-69.

[7] K. Satoh, S. Matsui, Y. Ito, K. Bessyo, R. Sakurai and S. Takahara, Determination of Preheating Conditions to Avoid Weld Cracking in Steel Const., IIW Doc. No. IX-730-71.

[8] K. Satoh, S. Matsui, and K. Horikawa: JSSC Guidance Report on Determination of Safe Preheating Conditions without Weld Cracks in Steel Structures, Transactions of JWRI, Vol. 2, No. 2 (1973).

[9] N. Bailey, Weldability of Ferritic Steels, Abington Publishing, England (1994).

[10] Kim H. J, Kang B. Y, Effect of Microstructural Variation on Weld Metal Cold Cracking of HSLA-100 Steel, ISIJ International Journal, vol. 43, no. 5 (2003), pp.706-713.

DOI: 10.2355/isijinternational.43.706

[11] J.S. Seo, H.J. Kim, H.S. Ryo, Microstructural Parameter Controlling Weld Metal Cold Cracking, Journal of Achievement in Materials and Manufacturing Engineering Volume 27 Issue 2, (2008), pp.199-202.