航空材料学报

EQUILIBRATED ALLOYING OF NICKEL-BASE SUPERALLOYS

G. E. Molozova

1993, 13(1): 1-4.

[Abstract](1503) [PDF 325KB](175)

Abstract:
The ultimate common solubility of aluminium and transitional elements in FCC lattce of nickel is depended upon the linear relationship between average atomic mass and concentration valence electrons of components. This rule is established on the law of equilibrated alloying, with its help and through simple calculation of degree and symbol of de-equilibriam the formation of detrimental compounds and elements segregation may be predicted in advance. Evaluating stability in this way gives a series of advantages by-comparison with phacomp and other variations. Regulation of equilibrated alloying may have wide use not only in applied metallurgical research, but also in phase condition study of new alloying systems.

INVESTIGATION ON CAST Ni₃Al BASE SUPERALLOY Ic-6

Li Sunhua, Han Yafang, Ma Sheng, Tan Yongning

1993, 13(1): 5-12.

[Abstract](1386) [PDF 694KB](143)

Abstract:
In this paper the relationship between chemical composition, microstructure and mechanical properties have been studied for the Ni3Al-base superalloys. The explored results show that the three elements, i. e. B, Al, Mo can have a significant influence on microstructure and mechanical properties in the Ni3Al-base superalloys. Control of γ sigle phase amount on microstructure has been discussed in the present investigation. The results indicate that the size and amount of γ’ sigle phase have a significant influence on mechanical properties. Strengthing mechanism of the Ni3Al base superalloy has been analyzed. It has been found that a certain amount of stable γ phase is necessary for excellent mechanical pro-perties of the Ni3Al base superalloys.

THE CAST-PHASES AND HOMOGENIZATION TREATMENTS OF THE LOW-EXPANSION SUPERALLOY GH907 AND GH909

Chen Qiong, Tian Shifan, Zhang Shaowei

1993, 13(1): 13-21.

[Abstract](1558) [PDF 926KB](566)

Abstract:
This paper introduces the casting precipitation properties, their effects on the alloy microstructure and the methods to eliminate the precipitation of the Low-expansion superalloy GH909. and GH907.

SURFACE ANALYSIS OF A PHTed SUPERALLOY POWDER

Yang Wanhong, Yu Kelan, Lai Heyi, Yan Minggao

1993, 13(1): 22-29.

[Abstract](1444) [PDF 758KB](195)

Abstract:
The surface composition and precipitates on the surface of heattreated Rene’95 powder were analyzed using ESCA and electron microscopy. Many ZrO2 particles are found. Primary carbides on the surface of argon atomized powder are transformed to MC of normal composition and structure. Carbides precipitated from saturated matrix are observed. These carbides are associated with oxides, which act as the nuclei for the carbides. The work shows that powder heat treatment (PHT) can neither reduce nor change precipitation on the surface.

STUDIES OF STRUCTURE AND PROPERTIES ON LIGHTLY CROSSLINKING ORGANIC GLASS

Wang Shanqi, Li Guizhi

1993, 13(1): 30-39.

[Abstract](1582) [PDF 1116KB](175)

Abstract:
In this paper, the chemical structure of aviation perspox have been modified by the copolymerization of two crosslinking agents (allyl methacrylate, diethylene glycol dimthacrylate) with methly methacrylate and methacrylic acid, and four lightly cross linking organic glass plates have been manufactured. Various tests, such as aging stability, heat—mechanical (tensile and impact) properties, transparence, stress—solvent crazing, degree of crosslinking, DMD and infrared spectra of these plates were evaluated and compared with aviation perspex YB3 and YB4 in structure and properties. The results of the studies show that all above—mentioned properties of modified plates is better than aviation perspex YB3 and YB4. So lightly copolymerization—crosslinking is the most effective method to improve heat—mechanical properties and aging—resistence of organic glass plates.

MECHANIC PROPERTY OF CARBON FIBERS AND WEIBULL MODEL

He Fu Liang, Tao Wang Rune

1993, 13(1): 40-46.

[Abstract](1430) [PDF 395KB](355)

Abstract:
Because carbon fibers belong to brittle materials, their mechanic properties such as tensile sttength depend on stochastic defects. The Weibull weakest linking model and empirical formula can express and calculate the relationship between tensile strength and cv value as well as the relationship between teasile strength and fiber dianeters. Meanwhile, we have put forward the method calculating the biparameter Weibull model with mutinomial regression. We also used direct—fitting method calculating the triparameter weibull model and obtained satisfied results.

DEVELOPMENT OF SECOND GENERATION DS COLUMN CRYSTAL SUPERALLOYS

Chen Rongzhang

1993, 13(1): 47-55.

[Abstract](1396) [PDF 541KB](222)

Abstract:
The second generation DS column crystal superalloys possess attractive combination of high temperature strength, excellent oxidation resistance and castability equivalent to that of the first generation single crystal superalloy such as PWAI480, CMSX—2. And, as airfoil alloys, the process cost and inspection cost are lower than that of single crystal. Therefore, the superalloys have been used as ideal candidate to replace some single crystal alloys in advanced military and commercial engines such as PWA2037,CF6-80C,In this paper the features of the alloy composition,heat treatment and properties have been reviewed.

1993 Vol. 13, No. 1