Mechanical Behavior of As-Cast and High Temperature Exposed Ni-Base Superalloy B1900

2004 ◽  
Vol 449-452 ◽  
pp. 541-544 ◽  
Author(s):  
I.S. Kim ◽  
Baig Gyu Choi ◽  
Seong Moon Seo ◽  
Chang Yong Jo
Keyword(s):  
High Temperature ◽  
Tensile Deformation ◽  
Rupture Life ◽  
Stress Rupture ◽  
Thermal Exposure ◽  
Tensile Specimen ◽  
Dislocation Network ◽  
Stress Rupture Life ◽  
Cast Specimen ◽  
Base Superalloy

Microstructural evolution during high temperature exposure and its effects on tensile and stress rupture properties of the Ni-base superalloy B1900 have been studied. Tensile deformation of the as-cast specimen was concentrated in the localized slip bands in general. Stacking faults and deformation twins were observed in the as-cast tensile specimen tested at 871°C where the alloy exhibited the lowest ductility. Dense dislocation network formed at γ/γ´ interface during thermal exposure caused homogenous deformation in the thermally exposed tensile specimen. Thermal exposure did not have significant effect on the stress rupture lives of the alloy at 760°C and at and above 871°C but it reduced stress rupture life of the alloy at 816°C γ´ coarsening and coherency loss at the γ/γ´ interface during thermal exposure were primarily responsible for the deterioration of mechanical properties and characteristic deformation behavior of the alloy.

High Temperature Rupture Life of Nickel-Based Superalloy under Directional Solidification with High Temperature Gradient

2017 ◽  
Vol 898 ◽  
pp. 422-429 ◽  
Author(s):  
Wei Guo Zhang ◽  
Zhi Jie Liu ◽  
Song Ke Feng ◽  
Fu Zeng Yang ◽  
Lin Liu
Keyword(s):  
High Temperature ◽  
Temperature Gradient ◽  
Directional Solidification ◽  
Temperature Stress ◽  
Solidification Rate ◽  
Rupture Life ◽  
Stress Rupture ◽  
High Temperature Stress ◽  
Stress Rupture Life ◽  
Nickel Based Superalloy

The stress rupture life of DZ125 nickel-based superalloy that was prepared by directional solidification process under the temperature gradient of 500 K/cm has been studied at 900°C and 235MPa. The results showed that with the increase of directional solidification rate from 50 μm/s to 800 μm/s, the primary dendrite arm spacing reduced from 94 μm to 35.8 μm and γ' precipitates reduced and more uniformed in size. The high temperature stress rupture life of as-cast sample increased firstly and then decreased and reached its maximum at the solidification rate of 500 μm/s. The dislocation configuration of sample with refine dendritic structure after stress rupture was investigated and discovered that the dislocations in different parts of sample had different morphology and density, which indicated that the deformation of as-cast samples were uneven during high temperature stress rupture. A lot of dislocations intertwined around carbides and at the interface of γ/γ', and the dislocation networks were destroyed and the dislocations entered γ' precipitate by the way of cutting.

Effect of heat treatment on microstructure and stress rupture life of DD32 single crystal Ni-base superalloy

2007 ◽  
Vol 460-461 ◽  
pp. 420-427 ◽  
Author(s):  
Jinjiang Yu ◽  
Xiaofeng Sun ◽  
Nairen Zhao ◽  
Tao Jin ◽  
Hengrong Guan ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Single Crystal ◽  
Rupture Life ◽  
Stress Rupture ◽  
Stress Rupture Life ◽  
Base Superalloy

High-Temperature, Cobalt-Tungsten Alloys for Aerospace Applications

1965 ◽  
Vol 87 (1) ◽  
pp. 9-20 ◽  
Author(s):  
J. C. Freche ◽  
R. L. Ashbrook ◽  
G. D. Sandrock
Keyword(s):  
High Temperature ◽  
Rupture Strength ◽  
Rupture Life ◽  
High Stress ◽  
Stress Rupture ◽  
Stress Rupture Life ◽  
Tungsten Alloys ◽  
Aerospace Applications ◽  
Temperature Capability ◽  
Nickel Base

The high-temperature capability and workability of cobalt-tungsten alloys for aerospace applications is discussed. The average life at 1850 F and 15,000 psi of the strongest previously reported alloy, Co-25 W-1Ti-1Zr-0.4C, was doubled from 92 to 185 hr by small additions of chromium and rhenium. At 2200 F and 5000 psi, the strongest alloy, Co-25W-1Ti-1Zr-3Cr-2Re-0.4C, had a rupture life of 23 hr; the elevated-temperature rupture strength compared favorably with the strongest available conventional (high-chromium) cobalt-base alloys. Above approximately 2035 F and at reasonably high stress levels (10,000 and 15,000 psi), its stress-rupture life also exceeded those of the strongest known nickel-base alloys, including the NASA tantalum-modified alloy and SM-200. It is particularly significant that even the strongest alloys of this series were readily hot-rolled. Ingots 1/2 in. thick were reduced to 0.065-in. sheet and subsequently cold-rolled to 0.0125-in. sheet. Elongations as high as 31 percent were obtained at room temperature with annealed sheet specimens. The good ductility obtained suggests that these alloys could be fabricated into complex shapes required for various aerospace and other applications. Although the strongest alloys had a chromium content of only 3 percent, they did not oxidize catastrophically in air.

EFFECTS OF CRYSTAL ORIENTATION ON STRESS RUPTURE BEHAVIOR OF A Ni3Al-BASE SINGLE CRYSTAL SUPERALLOY IC6SX

2010 ◽  
Vol 24 (15n16) ◽  
pp. 2952-2957
Author(s):  
LIWU JIANG ◽  
SHUSUO LI ◽  
MEILING WU ◽  
YAFANG HAN
Keyword(s):  
High Temperature ◽  
Single Crystal ◽  
Crystal Orientation ◽  
Rupture Life ◽  
Stress Rupture ◽  
High Temperature Stress ◽  
Stress Rupture Life ◽  
Area Reduction ◽  
Crystal Orientations ◽  
Rupture Behavior

The effect of the crystal orientation on the stress rupture behavior of the Ni 3 Al -base Single Crystal alloy IC6SX under the test condition of 1100°C/120Mpa has been studied. The results showed that the stress rupture lives of the specimens with [001], [011] and [111] crystal orientations were 205.45h, 268.6h and 485h, respectively, i.e., the specimen with [111] crystal orientation had the longest stress rupture life. The results of the tests also showed the significant different of high temperature stress rupture elongation and area reduction for different crystal orientation specimens, i.e., the ruptured elongations for the specimens with [001], [011] and [111] crystal orientations were 61.9%, 22.9% and 28.8%, and the values of area reduction for the specimens with [001], [011]and [111] crystal orientations were 11.7%, 12.2%and 7.3% respectively.

Influence of Carbides on Stress Rupture Property of a Ni-Base Superalloy

2016 ◽  
Vol 849 ◽  
pp. 520-525
Author(s):  
Zhen Rui Li ◽  
Ning An
Keyword(s):  
Rupture Life ◽  
High Stress ◽  
Stress Rupture ◽  
Fracture Morphology ◽  
Stress Rupture Life ◽  
Stress Rupture Property ◽  
Moderate Number ◽  
Carbide Size ◽  
Base Superalloy ◽  
Scanning Electron

This study aims to explore the influence of morphology and distribution characteristic of carbides on stress rupture property at high temperature. The stress rupture life at 850°C/325MPa was tested. Meanwhile, microstructure and fracture morphology of stress rupture specimens were observed by scanning electron microscopy. The types of carbides were identified and the carbide size was also measured. The results show that the alloys with small size, uniformly distribution and moderate number of carbides present a high stress rupture performance.

Stress Rupture Properties of the Second Generation Single Crystal Superalloy DD6 after High Temperature Exposure

2007 ◽  
Vol 546-549 ◽  
pp. 1249-1252 ◽  
Author(s):  
Hai Peng Jin ◽  
Jia Rong Li ◽  
Shi Zhong Liu
Keyword(s):  
High Temperature ◽  
Single Crystal ◽  
Second Generation ◽  
Rupture Life ◽  
Stress Rupture ◽  
Single Crystal Superalloy ◽  
Stress Rupture Life ◽  
Stress Rupture Properties ◽  
Temperature Exposure ◽  
Rupture Properties

The effects of high temperature exposure simulating service conditions on stress rupture properties were studied for the second generation single crystal superalloy DD6. The specimens with [001] orientation were exposed in air at temperatures of 980°C and 1070°C for 100h to 1000h. They were then tested using conventional mechanical tests at 1070°C/140MPa to determine the effects of exposure on stress rupture properties. The analysis indicated that stress rupture life decreased with increasing exposure time. At the temperature of 980°C, the stress rupture life is more than 180h after exposure for 1000h. When the test temperature increased to 1070°C, the stress rupture life exceeds 100h after 800h exposure. The morphology of γ prime phase after exposure was observed by using scanning electron microscopy (SEM). Morphologies evaluations have shown that alloy DD6 exhibits excellent microstructure stability after exposure. TCP (Topologically Closed Packed) phases have not been observed. It has been also found that the morphology and size of γ prime affected stress rupture life of the alloy. The decrement in stress rupture life with increasing exposure is a result of γ prime rafting.

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