The Paton Welding Journal, 2011, №12



2011 №12 (02)

2011 №12 (04)

---

The Paton Welding Journal, 2011, #12, 13-16 pages  

INVESTIGATION OF THERMOCHEMICAL CHARACTERISTICS OF MIXTURES OF DISPERSED MATERIALS BY DIFFERENTIAL THERMAL ANALYSIS METHODS

V.N. SHLEPAKOV and A.S. KOTELCHUK

E.O. Paton Electric Welding Institute, NASU, Kiev, Ukraine
 
 
Abstract
It is shown that formation of melts as early as at a stage of heating of the powder core up to melting of the sheath of a flux-cored wire and evolution of the gaseous products (H₂O, CO₂, SiF₄) determine shielding functions of an electrode material and exert a substantial effect on the course of metal to gas interaction reactions at the drop and pool stages. Temperature ranges of thermochemical reactions accompanying the heating process overlap, and their thermal effects superimpose on one another, thus stimulating development of some processes and slowing down the other ones. Control of these reactions by varying composition of a mixture allows regulation of the rate of melting of the core to achieve favourable characteristics of melting of the flux-cored wire and transfer of the electrode metal into the weld pool.
 
 
Keywords: electric arc welding, flux-cored wire, core composition, thermochemical processes, thermal analysis, thermogravimetry, differential scanning calorimetry
 
 
Received:                ??.??.??
Published:               28.12.11
 
 
References
1. Pokhodnya, I.K., Suptel, A.M., Shlepakov, V.N. (1972) Flux-cored wire welding. Kiev: Naukova Dumka.
2. Pokhodnya, I.K., Yavdoshchin, I.R., Paltsevich, A.P. et al. (2004) Metallurgy of arc welding: interaction of metal with gases. Ed. by I.K. Pokhodnya. Kiev: Naukova Dumka.
3. Erokhin, A.A. (1973) Principles of fusion welding. Physical-chemical mechanisms. Moscow: Nauka.
4. Killing, R. (1980) Welding with self-shielded wires – the mechanism of shielding and droplet transfer. Metal Constr., 12(9), 433-436.
5. Shlepakov, V.N. (1990) Kinetics of processes of interaction between metal and gases in flux-cored wire welding. Kiev: Naukova Dumka.
6. Shlepakov, V.N., Suprun, S.A., Kotelchuk, A.S. (1987) Kinetics of gas generation in flux-cored wire welding. IIW Doc. XII-1046-87.
7. (2003) Combined DSC-TGA Q600: User's manual. Moscow: Intertech Corp.
8. (2008) Prolab: Operation manual. Thermo Sci., Ion Path, Issue 7, July.
9. Shlepakov, V.N., Suprun, S.A., Kotelchuk, A.S. (1990) Estimating of the characteristics of flux-cored wire welding under the wind flow effect. In: Proc. of Int. Conf. on Welding under Extreme Conditions (Helsinki, Sept. 4-5, 1989). Oxford; New York: Pergamon Press, 171-179.

---

Suggested Citation

V.N. SHLEPAKOV and A.S. KOTELCHUK (2011) INVESTIGATION OF THERMOCHEMICAL CHARACTERISTICS OF MIXTURES OF DISPERSED MATERIALS BY DIFFERENTIAL THERMAL ANALYSIS METHODS. The Paton Welding J., 12, 13-16.

---