Effect of Surface Micromorphology on the Deformation and Bonding Quality of Stainless Steel/Carbon Steel during Hot Isostatic Pressing

A cylindrical indenter was designed to simulate the roller and 304 stainless steel / Q235A carbon steel plate with different roughness were bonded together. The interfacial bonding behavior was investigated by SEM, ultrasonic “C” scanning detection and nanoindentation test. The result reveal that with the increase of contact pressure between interfaces, the atoms of dissimilar metals begin to diffuse across interfaces in some regions, then form island-like bonding regions, and eventually extend to the whole interface. There are no obvious cracks on the surface of stainless steel and carbon steel after deformation. The cold roll-bonding mechanism of stainless steel and carbon steel is that elements on both sides of the interface diffuse and form a shallow diffusion layer under pressure to ensure the joint strength, and the joint bonding strength is greater than the strength of carbon steel matrix. In addition, the surface morphology of base metal has a great influence on the interfacial bonding quality. The higher surface roughness values increases the hardening degree of rough peak, which makes real contact area difficult to increase and reduce the interfacial bonding quality.

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On Hot Isostatic Pressing Sintering of Fused Filament Fabricated 316L Stainless Steel – Evaluation of Microstructure, Porosity, and Tensile Properties

Materials Letters ◽

10.1016/j.matlet.2021.129854 ◽

2021 ◽

pp. 129854

Author(s):

Yun Wang ◽

Li Zhang ◽

Xun Li ◽

Zhao Yan

Keyword(s):

Stainless Steel ◽

Tensile Properties ◽

316L Stainless Steel ◽

Hot Isostatic Pressing ◽

Isostatic Pressing

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Study on the Hot Deformation Characterization of Borated Stainless Steel by Hot Isostatic Pressing

Materials ◽

10.3390/ma14237110 ◽

2021 ◽

Vol 14 (23) ◽

pp. 7110

Author(s):

Yanbin Pei ◽

Xuanhui Qu ◽

Qilu Ge ◽

Tiejun Wang

Keyword(s):

Stainless Steel ◽

Hot Deformation ◽

True Strain ◽

Hot Isostatic Pressing ◽

Microstructural Analysis ◽

Critical Conditions ◽

True Strain Rate ◽

Isostatic Pressing ◽

Different Temperatures ◽

Borated Stainless Steel

Borated stainless steel (BSS) specimens have a boron content of 1.86 wt%, and are prepared by hot isostatic pressing (HIP) conducted at different temperatures, ranging from 1000 to 1100 °C and a constant true strain rate (0.01, 0.1, 1 and 10 s−1). These tests, with observations and microstructural analysis, have achieved the hot deformation characteristics and mechanisms of BSS. In this research, the activation energy (Q) and Zener–Hollomon parameter (Z) were contrasted against the flow curves: Q = 442.35 kJ/mol. The critical conditions associated with the initiation of dynamic recrystallization (DRX) for BSS were precisely calculated based on the function between the strain hardening rate with the flow stress: at different temperatures from 1000 to 1100 °C: the critical stresses were 146.69–254.77 MPa and the critical strains were 0.022–0.044. The facts show that the boron-containing phase of BSS prevented the onset of DRX, despite the saturated boron in the austenite initiated DRX. The microstructural analysis showed that hot deformation promoted the generation of borides, which differed from the initial microstructure of HIP. The inhomogeneous distribution of elements in the boron-containing phase was caused by hot compression.

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Producing HP Pump Barrels Utilizing Powder Metallurgy and Hot Isostatic Pressing

Volume 6: Materials and Fabrication, Parts A and B ◽

10.1115/pvp2009-77787 ◽

2009 ◽

Author(s):

Martin Bjurstro¨m ◽

Carl-Gustaf Hjorth

Keyword(s):

High Pressure ◽

Stainless Steel ◽

Stainless Steels ◽

Hot Isostatic Pressing ◽

Austenitic Stainless Steels ◽

Pressure Vessels ◽

Uniform Structure ◽

Isostatic Pressing ◽

Near Net Shape ◽

Hip Process

The fabrication of near net shape powder metal (PM) components by hot isostatic pressing (HIP) has been an important manufacturing technology for steel and stainless steel alloys since about 1985. The manufacturing process involves inert gas atomization of powder, 3D CAD capsule design, sheet metal capsule fabrication and densification by HIP in very large pressure vessels. Since 1985, several thousand tonnes of parts have been produced. The major applications are found in the oil and gas industry especially in offshore applications, the industrial power generation industry, and traditional engineering industries. Typically, the components replace castings, forgings and fabricated parts and are produced in high alloy grades such as martensitic steels, austenitic stainless steels, duplex (ferritic/austenitic) stainless steels and nickel based superalloys. The application of PM/HIP near net shapes to pump barrels for medium to high pressure use has a number of advantages compared to the traditional forging and welding approach. First, the need for machining of the components is reduced to a minimum and welding during final assembly is reduced substantially. Mechanical properties of the PM/HIP parts are isotropic and equal to the best forged properties in the flow direction. This derives from the fine microstructure using powder powder and the uniform structure from the HIP process. Furthermore, when using the PM HIP process the parts are produced near net shape with supports, nozzles and flanges integrated. This significantly reduces manufacturing lead-time and gives greater design flexibility which improves cost for the final component. The PM HIP near net shape route has received approval from ASTM, NACE and API for specific steel, stainless steel and nickel base alloys. This paper reviews the manufacturing sequence for PM near net shapes and discusses the details of several successful applications. The application of the PM/HIP process to high pressure pump barrels is highlighted.

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Producing HP Pump Barrels Utilizing Powder Metallurgy and Hot Isostatic Pressing

Volume 4: Design and Manufacturing ◽

10.1115/imece2009-11209 ◽

2009 ◽

Author(s):

Martin Bjurstro¨m ◽

Carl-Gustaf Hjorth

Keyword(s):

High Pressure ◽

Stainless Steel ◽

Stainless Steels ◽

Hot Isostatic Pressing ◽

Austenitic Stainless Steels ◽

Pressure Vessels ◽

Uniform Structure ◽

Isostatic Pressing ◽

Near Net Shape ◽

Hip Process

The fabrication of near net shape powder metal (PM) components by hot isostatic pressing (HIP) has been an important manufacturing technology for steel and stainless steel alloys since about 1985. The manufacturing process involves inert gas atomization of powder, 3D CAD capsule design, sheet metal capsule fabrication and densification by HIP in very large pressure vessels. Since 1985, several thousand tonnes of parts have been produced. The major applications are found in the oil and gas industry especially in offshore applications, the industrial power generation industry, and traditional engineering industries. Typically, the components replace castings, forgings and fabricated parts and are produced in high alloy grades such as martensitic steels, austenitic stainless steels, duplex (ferritic/austenitic) stainless steels and nickel based superalloys. The application of PM/HIP near net shapes to pump barrels for medium to high pressure use has a number of advantages compared to the traditional forging and welding approach. First, the need for machining of the components is reduced to a minimum and welding during final assembly is reduced substantially. Mechanical properties of the PM/HIP parts are isotropic and equal to the best forged properties in the flow direction. This derives from the fine microstructure using powder powder and the uniform structure from the HIP process. Furthermore, when using the PM HIP process the parts are produced near net shape with supports, nozzles and flanges integrated. This significantly reduces manufacturing lead-time and gives greater design flexibility which improves cost for the final component. The PM HIP near net shape route has received approval from ASTM, NACE and API for specific steel, stainless steel and nickel base alloys. This paper reviews the manufacturing sequence for PM near net shapes and discusses the details of several successful applications. The application of the PM/HIP process to high pressure pump barrels is highlighted.

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