Fabrication of carbon-carbon composites by using hot isostatic pressing technology and novel precursor materials

Since the introduction of hot isostatic pressing (HIP) technology, it has been widely used in powder metallurgy forming and improving the densification of castings. With the increasing demand for the performance of nickel-based single crystal superalloy, more and more scholars started research on the application of hot isostatic pressing in nickel-based single crystal superalloy. This article summarizes the current research progress in the application of hot isostatic pressing to the high temperature of nickel-based single crystals, explains the elimination effect of hot isostatic pressing on porosity and other pore defects in nickel-based single crystal superalloy, analyzes the pore healing mechanism, and the changes in mechanical properties such as tensile, endurance, and fatigue of the alloy after applying hot isostatic pressing are shown. Finally, the future development of China’s hot isostatic pressing technology is prospected.

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Development of Hot Isostatic Pressing Technology for Investment Cast Products

Materials Science Forum ◽

10.4028/www.scientific.net/msf.830-831.19 ◽

2015 ◽

Vol 830-831 ◽

pp. 19-22

Author(s):

S. Dineshraj ◽

Mayukh Acharya ◽

Alok Agarwal ◽

S. Girikumar ◽

Govind ◽

...

Keyword(s):

Hot Isostatic Pressing ◽

Microstructural Analysis ◽

Quality Requirements ◽

Isostatic Pressing ◽

Defect Healing ◽

Aerospace Applications ◽

Before And After ◽

Steel Cast ◽

Stringent Quality ◽

Pressing Technology

Hot isostatic pressing (HIPping) technology is used for healing the casting defects for aerospace applications. Castings used for aerospace applications like turbo-pumps need to meet very stringent quality requirements. Complexity of the castings used in these applications, makes it difficult to meet the quality requirements in all the areas. Defects like gas holes, shrinkages, cavities etc. may occur in few locations and need to be repaired by welding or healed by HIPping. In the present study, we attempted to simulate the defect healing capability of HIP in a systematic manner. Artificial defects were created in Austenite-Martensite grade stainless steel cast rod. These rods were then subjected to HIP prcoss cycle at 1150 °C and at a pressure of 1620 bar. Healing of the defects was ensured through X-ray radiography. Detailed microstructural analysis using optical metallography and scanning electron microscopy (SEM) with EDX was carried out before and after HIPping, to understand the defect healing mechanisms. These results are discussed in detail here.

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Study on Direct Hot Isostatic Pressing Technology for Superalloy Inconel 625

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.189-193.2935 ◽

2011 ◽

Vol 189-193 ◽

pp. 2935-2938 ◽

Cited By ~ 6

Author(s):

Ji Wei Wang ◽

Qing Song Wei ◽

Guo Cheng Liu ◽

Yu Kun He ◽

Yu Sheng Shi

Keyword(s):

Room Temperature ◽

Hot Isostatic Pressing ◽

Tensile Tests ◽

Inert Gas ◽

Inconel 625 ◽

Full Density ◽

Fracture Surface Morphology ◽

Structure And Properties ◽

Isostatic Pressing ◽

Pressing Technology

Inert gas atomized (IGA) superalloy Inconel 625 powder was consolidated by hot isostatic pressing (HIPing) directly under the HIPing parameters of 1100°C/110MPa/3h. The structure and properties of the as–HIPed samples were investigated using optical microscopy (OM), scanning electron microscopy (SEM) and tensile tests at room temperature, and its relative density was measured by drainage. The fracture surface morphology of the tensile specimens have been investigated using SEM. The results showed that full density alloy can be obtained under the HIPing parameters of 1100°C/110MPa/3h. Due to the effect of prior particle boundaries (PPBs), the strength of the as-HIPed alloy is comparatively high, but its ductibility is comparatively low.

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Effect of hot isostatic pressing technology on structure and properties of products made of VZh159 heat-temperature alloy

Blanking productions in mechanical engineering (press forging, foundry and other productions) ◽

10.36652/1684-1107-2021-19-1-44-48 ◽

2021 ◽

pp. 44-48

Author(s):

A.A. Khlybov ◽

E.S. Belyaev ◽

A.D. Ryabtsev ◽

S.S. Belyaeva ◽

Yu.A. Getmanovsky ◽

...

Keyword(s):

Fractional Composition ◽

Cast Alloy ◽

Hot Isostatic Pressing ◽

Structure And Properties ◽

Heat Temperature ◽

Isostatic Pressing ◽

Powder Body ◽

Metallic Inclusions ◽

Process Documentation ◽

Pressing Technology

The hot isostatic pressing (HIP) technology is considered on the example of making of compacts made of VZh159 powder. It is shown that powders with fractional composition of –70 +25 µm, bulk density of 3.77 g/cm3 , fl uidity of 2.3 g/s, specifi c surface of 446 cm2 /g, and average Fischer particle size of 16 µm are prone to sorbed gases. Gases on the surface of the powder body as result of the HIP cycle can form non-metallic inclusions that reduce the properties of the compact. To effectively remove gases, vacuum heat treatment is used: degassing. It is established that the structure of HIP-compacts after two- or four-stage ageing has fi ner grain (point 9) compared to the cast alloy (point 7).The mechanical properties of the compacts obtained made of VZh159 power exceed the correspointing requirements of the standard process documentation for ultimate strength by 21...22 % and elongation by 36...45 %.

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