Development of an austenitic chromium-manganese steel with high hydrogen resistance
- PDF / 283,634 Bytes
- 7 Pages / 612 x 792 pts (letter) Page_size
- 90 Downloads / 164 Views
DEVELOPMENT OF AN AUSTENITIC CHROMIUM–MANGANESE STEEL WITH HIGH HYDROGEN RESISTANCE V. I. Tkachov, L. M. Ivas’kevych, and V. I. Vytvyts’kyi
UDC 620.172:669.786
We compare the results of studying the effect of hydrogen on the characteristics of short-time strength and low-cycle durability of austenitic stainless steels and age-hardening alloys. We show that austenitic stainless 06Kh20N16G6AF steel with solid-solution strengthening and the optimal content of nickel, manganese, and nitrogen possesses high mechanical characteristics and is least inclined to hydrogen degradation.
The use of hydrogen as an ecologically pure fuel is hampered significantly due to the hydrogen embrittlement of structural materials. To prevent this phenomenon, a series of measures limiting the interaction of hydrogen atmosphere with metals was developed. Among them, one should mention the application of protective metal coatings or oxide films [1, 2], the introduction of active gaseous inhibiting admixtures [1, 3], and the decrease in the working parameters of gaseous hydrogen (pressure and temperature) [1, 3]. Another way of preventing hydrogen embrittlement is connected with the homogenization of the structure of materials by the methods of refining [1] and powder metallurgy [4] or with the formation of a certain dislocation structure, type, morphology, and distribution of strengthening phases [1, 3 – 6]. The rational alloying of steel affects efficiently the intensity of hydrogenation and diffusion processes [7] as well as the structural state of the material [8 – 10]. In the present paper, we optimize the chemical composition of austenitic chromium–manganese steel for operation in hydrogen. Materials and Experimental Procedure We systematized the results of investigations of the hydrogen influence on the mechanical properties of structural materials for hydrogen power engineering [1, 4, 11]. In particular, we considered low-carbon martensitic 03Kh12N10MT steel of vacuum-arc remelting, stable (Kh18N22V2T2, 03Kh13N9G19AM2, and 07Kh13G20AN4) and unstable (12Kh18N10T and 06Kh18N5G9AB) austenitic steels with solid-solution strengthening as well as age-hardening KhN23MTR, KhN43MBTYu, KhN55MBYu, and KhN60K16MBYu alloys with different concentrations of iron and nickel, strengthened by the intermetallic γ′-phase of the type of (Ni, Fe, Cr) 3 (Al, Ti, Nb). We evaluated the degree of hydrogen degradation by the effect of gaseous hydrogen on the standard mechanical tensile properties and low-cycle fatigue of the steels. We stretched smooth five-fold cylindrical specimens of diameter 5 mm and specimens with a notch of radius 0.1 mm at its tip. The stretching rate was 0.1 mm / min. The low-cycle durability under zero-to-pure bending with a strain amplitude of 1.6% and a frequency of 0.5 Hz was studied on plane specimens of cross section 2 × 6 mm2 and length 20 mm. Karpenko Physicomechanical Institute, Ukrainian Academy of Sciences, Lviv. Translated from Fizyko-Khimichna Mekhanika Materialiv, Vol. 41, No. 5, pp. 95 – 100, September – October, 2005.
Data Loading...
