Microstructure/Property Examination of Weld HAZ in Grade 100 Microalloyed Steel

2002 ◽  
Author(s):  
K. Poorhaydari ◽  
B. M. Patchett ◽  
D. G. Ivey
Keyword(s):  
Mechanical Properties ◽  
Mechanical Property ◽  
Filler Metal ◽  
Microalloyed Steel ◽  
Welding Process ◽  
Grain Structure ◽  
Property Variation ◽  
Weld Thermal Cycle ◽  
Transmission Electron ◽  
The Relationship

The weld thermal cycle in microalloyed pipeline and structural steels results in significant changes in microstructure and, consequently, mechanical properties of the weld heat-affected zone (HAZ). To have better control of the properties of the HAZ, knowledge of these changes and correlation with mechanical property variations is required. The first step in achieving this is to construct a methodology to examine different regions of the HAZ thoroughly, so that important characteristics such as grain size, microstructure, precipitate type and distribution, and mechanical properties are determined. The next step would be using this methodology to examine different regions of the HAZ under different welding conditions (the most important of which is heat input) and therefore to understand the effects of the welding process. In this paper, a methodology for studying HAZ microstructure/property relationships is demonstrated for a Grade 100 microalloyed steel welded autogenously (no filler metal). Microhardness measurements are used to assess the mechanical property variation across the HAZ. Optical microscopy (OM) and transmission electron microscopy (TEM) are used for grain structure examination and precipitate analysis. The relationship between microstructure and mechanical properties, with emphasis on precipitate reactions, is presented for different regions of the HAZ.

Mechanical Properties and Microstructure Evolution of Typical Over-Aging State Al-Zn-Mg-Cu Alloy during Thermal Exposure

2021 ◽  
Vol 1026 ◽  
pp. 84-92
Author(s):  
Tao Qian Cheng ◽  
Zhi Hui Li
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Mechanical Property ◽  
Electrical Conductivity ◽  
Transmission Electron Microscopy ◽  
Tensile Strength ◽  
Thermal Exposure ◽  
Cu Alloy ◽  
Transmission Electron ◽  
Thermal Stability Of

Al-Zn-Mg-Cu alloy have been widely used in aerospace industry. However, there is still a lack of research on thermal stability of Al-Zn-Mg-Cu alloy products. In the present work, an Al-Zn-Mg-Cu alloy with T79 and T74 states was placed in the corresponding environment for thermal exposure experiments. Performance was measured by tensile strength, hardness and electrical conductivity. In this paper, precipitation observation was analyzed by transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HREM). The precipitations of T79 state alloy were GPⅡ zone, η' phase and η phase while the ultimate tensile strength, hardness and electrical conductivity were 571MPa, 188.2HV and 22.2MS×m-1, respectively. The mechanical property of T79 state alloy decreased to 530MPa and 168.5HV after thermal exposure. The diameter of precipitate increased and the precipitations become η' and η phase at the same time. During the entire thermal exposure, T74 state alloy had the same mechanical property trend as T79 state alloy. The precipitate diameter also increased while the types of precipitate did not change under thermal exposure. The size of precipitates affected the choice of dislocation passing through the particles to affect the mechanical properties.

The Dislocation Patterns in Deformed Metals: Dislocation Densities, Distributions and Related Misorientations

2007 ◽  
Vol 550 ◽  
pp. 193-198
Author(s):  
Edgar F. Rauch ◽  
G. Shigesato
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Transmission Electron Microscopy ◽  
Dislocation Substructure ◽  
Metals And Alloys ◽  
The Past ◽  
Transmission Electron ◽  
Dislocation Densities ◽  
Broad Variety ◽  
The Relationship

The dislocation substructure that appears in deformed metals and alloys have been extensively investigated in the past by transmission electron microscopy (TEM). They are known to form a broad variety of microstructures. These substructures are characterized by three main parameters, namely the density of the dislocations that are trapped in the tangles, their degree of patterning and the misorientation between the cells. The aim of the present work is to investigate the relationship between these features and the mechanical properties of the material.

Study on the Relationship between Microscopic Structure and Mechanical Properties of HTPB Propellant

2010 ◽  
Vol 152-153 ◽  
pp. 1151-1155 ◽  
Author(s):  
Xu Chang Li ◽  
Jian Jiao ◽  
Jun Yan Yao ◽  
Liang Wang
Keyword(s):  
Mechanical Properties ◽  
Mechanical Property ◽  
Cross Section ◽  
Structural Integrity ◽  
Solid Particles ◽  
Microscopic Structure ◽  
Structure State ◽  
Htpb Propellant ◽  
The Relationship ◽  
Bond Effect

By means of a tensile instrument and SEM, the mechanical property parameters of HTPB propellant test samples with different formulas were tested, and their microscopic fracture cross section patterns were observed. Take advantage of these testing results, the relationship between microscopic structure and mechanical properties of HTPB propellant was studied. The results show that the mechanical properties of a propellant are closely related to its microscpic structure state. The structural integrity of propellant is mainly influenced by the bond effect of the interface between binder and solid particles, solid particle’s shape, size and its distribution, the content of binder matrix, etc. These factors have important effects on the mechanical properties of propellant.

Effect of Annealing Temperature on Microstructure and Properties of Ultra Purified Ferritic Stainless Steel Containing Copper

2018 ◽  
Vol 913 ◽  
pp. 270-276
Author(s):  
Hong Xiang Yin ◽  
Yi Wu ◽  
Ai Min Zhao ◽  
Zheng Zhi Zhao ◽  
Qiu Qin Fu
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Annealing Temperature ◽  
Texture Evolution ◽  
Fiber Texture ◽  
Transmission Electron ◽  
Back Scattering ◽  
Higher Temperature ◽  
Means Of Transmission ◽  
The Relationship

The effects of annealing temperature on microstructure, mechanical properties, formability, and texture evolution were analyzed in the article. The microstructure of the steel obtained through different annealing processes were investigated by means of transmission electron microscopy; The micro texture of steel was measured by using electron back scattering diffraction analysis; The relationship between Cu precipitates and matrix was analyzed by using the selected area diffraction technology. The results show that when annealing temperature was 700 ~ 850 °C, the yield strength and tensile strength first decreased slightly and then increased, while the elongation accordingly first increased then decreased slightly. The best mechanical property and formability were obtained at 800 °C. Cu precipitates reduced with the increase of annealing temperature and it accorded with K - S relationship with matrix. The grains near the {111} < 112 > orientation grew up selectively. The higher the temperature, the more the γ fiber texture content. But at higher temperature (850 °C), γ texture was damaged and the content was reduced.

Effects of Thermal Treatment on the Morphology and Properties of CSM/Poly(Urethane-Isocyanurate) Composites Formed by SRIM Process

2008 ◽  
Vol 575-578 ◽  
pp. 941-946
Author(s):  
Hong Yan Tang ◽  
Ji Hui Wang ◽  
Guo Qiang Gao ◽  
Wen Xing Chen
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Mechanical Property ◽  
Thermal Analysis ◽  
Scanning Electron Microscopy ◽  
Treatment Time ◽  
Microphase Separation ◽  
Scanning Calorimetry ◽  
Transmission Electron ◽  
Scanning Electron

Fiberglass continuous strand mat(CSM)/poly(urethane-isocyanurate) composites were formed by SRIM process, treated under different conditions and then characterized based on dynamic mechanical thermal analysis (DMTA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) ,transmission electron microscopy (TEM) and the mechanical property tests. The results show that the mechanical properties of the composites could be increased with improving the degree of microphase separation. At a given temperature (120°C), the degree of microphase separation is the highest for 4h and decreases gradually with prolonging treatment time. For a given time (4h), the well microphase-separated morphology is obtained and the degree of microphase mixing is increased at 120°C and 140°C treatments, respectively. The degree of microphase separation of the composites decreases with enhancing the temperature to 140°C.

scholarly journals Mechanical Properties and Microstructure Evolution of Mg-6 wt % Zn Alloy during Equal-Channel Angular Pressing

Metals ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 841 ◽  
Author(s):  
Jingli Yan ◽  
Zijun Qin ◽  
Kai Yan
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Grain Refinement ◽  
Equal Channel Angular Pressing ◽  
Testing Machine ◽  
Grain Structure ◽  
X Ray Diffraction ◽  
Angular Pressing ◽  
Transmission Electron ◽  
Zn Alloy

Equal-channel angular pressing (ECAP) was performed on a Mg (6 wt %) Zn alloy at temperatures from 160 to 240 °C and the microstructures and mechanical properties were studied using optical microscopy, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and an electronic universal testing machine. The results showed that ECAP was effective for grain refinement and a bi-modal grain structure formed at low temperatures, which was stable during ECAP from 160 to 200 °C. MgZn2 phase and Mg4Zn7 phase were generated during the ECAP process. The mechanical properties remarkably increased after two repetitions of ECAP. However, the strengths could not be further improved by increasing the plastic deformation, but decreased when ECAP was performed between 200 and 240 °C. The mechanical properties of the ECAP Mg-6Zn alloy was determined by a combination of grain refinement strengthening, precipitation hardening, and texture softening.

Impact of Grain Structure and Material Properties on Via Extrusion in 3-D Interconnects

2014 ◽  
Vol 2014 (1) ◽  
pp. 000008-000012
Author(s):  
Tengfei Jiang ◽  
Chenglin Wu ◽  
Jay Im ◽  
Rui Huang ◽  
Paul S. Ho
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Analytical Model ◽  
Material Properties ◽  
Grain Structure ◽  
Silicon Vias ◽  
The Relationship

In this paper, the effects of Cu microstructure on the mechanical properties and extrusion of though-silicon vias (TSVs) were studied based on two types of TSVs with different microstructure. A direct correlation was found between the grain size and the mechanical properties of the vias. Both an analytical model and FEA were used to establish the relationship between the mechanical properties and via extrusion. The effect of via/Si interface on extrusion was also studied by FEA. The results suggest small and uniform grains in the Cu vias, as well as stronger interfaces between the via and Si led to smaller via extrusion, and are thus preferable for reduced via extrusion failure and improved TSV reliability.

Impact of Grain Structure and Material Properties on Via Extrusion in 3D Interconnects

2015 ◽  
Vol 12 (3) ◽  
pp. 118-122 ◽  
Author(s):  
Tengfei Jiang ◽  
Chenglin Wu ◽  
Jay Im ◽  
Rui Huang ◽  
Paul S. Ho
Keyword(s):  
Mechanical Properties ◽  
Finite Element Analysis ◽  
Grain Size ◽  
Finite Element ◽  
Analytical Model ◽  
Material Properties ◽  
Grain Structure ◽  
Element Analysis ◽  
Silicon Vias ◽  
The Relationship

In this article, the effects of Cu microstructure on the mechanical properties and extrusion of through-silicon vias (TSVs) were studied based on two types of TSVs with different microstructure. A direct correlation was found between the grain size and the mechanical properties of the vias. Both an analytical model and finite element analysis (FEA) were used to establish the relationship between the mechanical properties and via extrusion. The effect of via/Si interface on extrusion was also studied by FEA. The results suggest small and uniform grains in the Cu vias, as well as stronger interfaces between the via and Si led to smaller via extrusion, and are thus preferable for reduced via extrusion failure and improved TSV reliability.

Finite Element Analysis of the Bionic Tissue Engineering Scaffold for the Defect Cranium

2012 ◽  
Vol 184-185 ◽  
pp. 222-226
Author(s):  
Fan Fen Peng ◽  
Shu Xian Zheng ◽  
Jia Li
Keyword(s):  
Mechanical Properties ◽  
Mechanical Property ◽  
Tissue Engineering ◽  
Finite Element Analysis ◽  
Tissue Engineering Scaffold ◽  
Element Analysis ◽  
Engineering Technology ◽  
Bionic Scaffold ◽  
Bottle Neck ◽  
The Relationship

The relationship between the porosity and the mechanical property was still a bottle-neck in bone tissue engineering scaffold. Porosity increasing may reduce the scaffold strength. In order to solve the contradiction, the idea of enhancing the mechanical properties by controlling the scaffold porosity was proposed in this paper. Using reverse engineering technology, 5 different porosity cranium scaffolds were first established. Their FE models were built through FE surface preprocessing and volume fitted meshing. According to results of static analysis, the displacements and stresses of the 5 porosity scaffolds were compared and discussed and it indicated that the 36% porosity bionic scaffold have good porous level and mechanical properties.

Characterization of Microstructure and Mechanical Properties of a Nb-Microalloyed Steel after Quenching-Partitioning-Tempering Process

2010 ◽  
Vol 654-656 ◽  
pp. 90-93 ◽  
Author(s):  
Xiao Dong Wang ◽  
Zheng Hong Guo ◽  
Yong Hua Rong
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Heat Treatment ◽  
Treatment Process ◽  
Microalloyed Steel ◽  
Heat Treatment Process ◽  
Step Process ◽  
Transmission Electron ◽  
Nb Microalloyed Steel ◽  
Tempering Process

A novel heat treatment process, that is, quenching-partitioning-tempering (Q-P-T) process, has been developed as a new way to obtain ultrahigh strength martensitic structural steel containing retained austenite and alloying carbide. In order to display merit of the Q-P-T process, a medium carbon Nb-microalloyed steel is treated by Q-P-T 1-step process and Q-P-T 2-step process, as well as treated by the transformation induced plasticity heat treatment process and quenching and tempering process, respectively. The results show that Q-P-T samples possess better mechanical properties than those treated by other heat treatment processes. The origin of the good mechanical properties is analyzed based on the phase and microstructure characterization using X-ray diffraction, scanning electron microscopy and transmission electron microscopy.

Sign in / Sign up

Export Citation Format

Share Document