Neck-and-Split Tensile Fracture of Anisotropic Plate Steel

1969 ◽  
Vol 91 (1) ◽  
pp. 39-43 ◽  
Author(s):  
W. R. Clough ◽  
J. L. Solomon
Keyword(s):  
Rolling Direction ◽  
Void Formation ◽  
Testing Temperature ◽  
Tensile Fracture ◽  
Plate Steel ◽  
Electron Fractography ◽  
Alloy Plate ◽  
Temperature Ranges ◽  
Longitudinal Split ◽  
Distinct Temperature

Rolling-direction tensile specimens of 0.31 C quenched and tempered alloy plate steel displayed cup-and-cone, split-layered, neck-and-split, and square-break fracture configurations over distinct temperature ranges as testing temperature was lowered from 300 to −320 F. Formation of the neck-and-split configuration was investigated in terms of stress state, temperature, void formation, and anisotropy. Electron fractography identified quasicleavage as the fracture mode of the initially occurring longitudinal split. The brittle fracture phenomenon resulting in the neck-and-split fracture of plate specimens occurs under a unique combination of conditions.

The Split, Layered, Cup-and-Cone Tensile Fracture

1968 ◽  
Vol 90 (1) ◽  
pp. 8-12 ◽  
Author(s):  
R. J. Hrubec ◽  
L. A. Jackman ◽  
W. R. Clough
Keyword(s):  
Flat Plate ◽  
Tensile Testing ◽  
Stress Conditions ◽  
Tensile Fracture ◽  
Plate Steel ◽  
Electron Fractography ◽  
Longitudinal Cracks

Quenched and tempered plate steel is capable of modified cup-and-cone fractures involving one or more longitudinal cracks “parallel” to the flat plate surfaces. The occurrence was verified by tensile testing of three steels at a variety of temperatures. Electron fractography revealed that quasi-cleavage, shear lips, tearing, and normal rupture were active, being identified by modified river patterns and by elongated and equiaxed dimples resulting from the coalescence of microvoids. The brittle longitudinal cracks are formed shortly before final rupture. Application of the Bridgman plasticity solution for necked tensile specimens shows that the split, layered, fracture occurs under unique stress conditions.

MTD 3

Alloy Digest ◽  
2017 ◽  
Vol 66 (9) ◽  
Keyword(s):  
Heat Treating ◽  
Plate Steel ◽  
Alloy Plate ◽  
Plate Steels

Abstract MTD 3 is a Mn-Cr-Mo-V plate steel used in cavity molds. ArcelorMittal USA MTD steels comprise a family of prehardened alloy plate steels developed for a variety of mold, tool, and die applications. This datasheet provides information on composition. It also includes information on forming, heat treating, machining, and joining. Filing Code: SA-798. Producer or source: ArcelorMittal USA, Plate.

scholarly journals Microstructure and Mechanical Properties of Thick Plate Friction Stir Welds for 6082-T6 Aluminum Alloy

2019 ◽  
Vol 38 (2019) ◽  
pp. 525-532 ◽  
Author(s):  
Zhimin Liang ◽  
Xue Wang ◽  
Congwei Cai ◽  
Dianlong Wang
Keyword(s):  
Aluminum Alloy ◽  
Thick Plate ◽  
Frictional Heating ◽  
High Heat ◽  
Tensile Fracture ◽  
Alloy Plate ◽  
Friction Stir ◽  
Welding Joint ◽  
High Heat Input ◽  
Two Sides

Abstract6082-T6 aluminum alloy plate with thickness of 42mm was butt welded by friction stir welding (FSW) from two sides. The microstructures of the joints exhibited different grain sizes because of unequal frictional heating and plastic flow during FSW process. The transition from the heat affected zone (HAZ) to the nugget zone (NZ) in thermos-mechanical affected zone of advancing side (AS-TMAZ) was more sudden than thermos-mechanical affected zone of retreating side (RS-TMAZ). Kissing bond (KB) defect throughout the entire FSW joint was displayed both at the grain boundary and in the interior of the grain with semi-continuous bands. KB had no direct effect on tensile properties. Vickers hardness of the FSW joint was lower than the BM because its high heat input, dissolved and coarsened precipitates and little to the grain size after FSW. Hardness distribution of double-sided welding joint showed X-shaped area softening characteristics, that is to say the lowest hardness was the junction of two welding joint of NZ and the junction of TMAZ and HAZ. The tensile fracture position occurred in the lowest hardness region of the FSW joint, and it did not occur in the KB defect position.

Hydrogen Production via the Iron/Iron Oxide Looping Cycle

2011 ◽  
Author(s):  
A. Singh ◽  
F. Al-Raqom ◽  
J. Klausner ◽  
J. Petrasch
Keyword(s):  
Iron Oxide ◽  
Hydrogen Production ◽  
Gas Phase ◽  
Energy Content ◽  
Operation Conditions ◽  
Iron Oxide Reduction ◽  
Temperature Ranges ◽  
Iron Iron ◽  
Gas Phase Separation ◽  
Distinct Temperature

The iron/iron-oxide looping cycle has the potential to produce high purity hydrogen from coal or natural gas without the need for gas phase separation: Hydrogen is produced from steam oxidation of iron or Wustite yielding primarily Magnetite; Magnetite is then reduced back to iron/Wustite using syngas (CO+H2). A system model has been developed to identify favorable operation conditions and process configurations. Process configurations for three distinct temperature ranges, (i) 500–950 K, (ii) 950–1100 K, and (iii) 1100–1200 K have been developed. The energy content of high temperature syngas from conventional coal gasifiers is sufficient to drive the looping process throughout the temperature range considered. Temperatures around 1000 K are advantageous for both the hydrogen production step and the iron oxide reduction step. Simulations of a large number of subsequent cycles indicate that quasi-steady operation is reached after approximately 5 cycles. Comparison of simulations and experiments indicate that the process is currently limited by chemical kinetics at lower temperatures. Therefore, product recirculation should be used for a scaled-up process to increase reactant residence times while maintaining sufficient fluidization velocity.

scholarly journals Behavior of Dynamic Strain Aging in Zr-1.5Nb-0.4Sn-0.2Fe-0.1Cr Alloy Strip

2021 ◽  
Vol 59 (1) ◽  
pp. 8-13
Author(s):  
Il-Hyun Kim ◽  
Myung-Ho Lee ◽  
Yang-Il Jung ◽  
Hyun-Gil Kim ◽  
Jae-Il Jang
Keyword(s):  
Tensile Test ◽  
Strain Rate ◽  
Dynamic Strain Aging ◽  
Strain Aging ◽  
Rolling Direction ◽  
Rate Sensitivity ◽  
Dynamic Strain ◽  
Alloy Strip ◽  
Lower Strain ◽  
Temperature Ranges

The behavior of dynamic strain aging (DSA) in a Zr-1.5Nb-0.4Sn-0.2Fe-0.1Cr alloy strip was investigated at temperature ranges of 25–600 °C via a tensile test. The tensile test was performed at two different strain rates 8.33 × 10<sup>-5</sup> and 1.67 × 10<sup>-2</sup> s<sup>-1</sup>. The shear stress of the alloy strip revealed a linear dependency on the test temperature when the specimens were tested under a higher strain rate (1.67 × 10<sup>-2</sup> s<sup>-1</sup>). However, the linear relationship was broken due to DSA when the samples were deformed under a lower strain rate (8.33 × 10<sup>-5</sup> s<sup>-1</sup>). The discrepancy was most significant at 400 °C. The trend in DSA behavior was similar irrespective of the orientation of the samples, i.e., rolling direction (RD) or transverse direction (TD). However, the effect of DSA was larger in the TD samples than the RD samples. The phenomena were interpreted to the variation in work hardening exponents and strain rate sensitivity. The value of the exponent decreased from 0.14 to 0.08 along a RD and from 0.1 to 0.07 along a TD, respectively. However, the smallest value was observed at 400–500 °C irrespective of the specimen orientation, which is consistent with the DSA behavior. It is suggested that the DSA was caused by an interaction of moving dislocations with solute atoms typically oxygen.

Effect of heat treatment schedules on the resistance to brittle failure of low-alloy plate steel 09G2S

1990 ◽  
Vol 32 (12) ◽  
pp. 891-895
Author(s):  
V. M. Goritskii ◽  
G. R. Shneiderov ◽  
T. G. Zaitseva
Keyword(s):  
Heat Treatment ◽  
Brittle Failure ◽  
Plate Steel ◽  
Alloy Plate ◽  
Steel 09G2s

Effects of Homogenization-Free on the Microstructures of an Al-Mg-Si-Cu Hot-Rolled Plate for Automotive Pannel

2018 ◽  
Vol 941 ◽  
pp. 1529-1534
Author(s):  
Ni Tian ◽  
Qi Long Liu ◽  
Zi Yan Zhao ◽  
Gang Zhao ◽  
Kun Liu
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Aluminum Alloy ◽  
Rolling Direction ◽  
Rolled Plate ◽  
Alloy Plate ◽  
Solution Treated ◽  
Aluminum Alloy Plate ◽  
Hot Rolled ◽  
Scanning Electron

The microstructure of Al-1.01Mg-1.11Si-0.38Cu-0.69Mn aluminum alloy plate hot-rolled from homogenization and homogenization-free ingots were investigated by optical microscopy and scanning electron microscopy assisted with energy dispersive spectroscopy (SEM/EDS). The results showed that there are 3 main kinds of constituents such as Mg2Si, AlCuMgSi and AlFeMnSi in the as-cast Al-1.01Mg-1.11Si-0.38Cu-0.69Mn aluminum alloy ingot. After homogenization treated at 545°C for 24h, the black Mg2Si and the white bright AlCuMgSi particles in the ingot dissolved into matrix, but the grey AlFeMnSi phase partly dissolved, contracted into sphere and become coarse, many ultrafine dispersoids appear in the dendritic arms. The constituents in the plates hot-rolled from the homogenization and homogenization-free ingots are both distributed as broken chains along the rolling direction. However, compared with the particles configuration in the plate that hot-rolled from homogenization ingot, the particles in the plate that hot-rolled from the homogenization-free ingot are finer, more numerous and more homogenous, and with insufficient recrystallization when the plates are solution treated at 545°C for 2 h and then water quenched.

Tensile fracture and fractographic analysis of 1045 spheroidized steel under hydrostatic pressure

1990 ◽  
Vol 5 (1) ◽  
pp. 83-91 ◽  
Author(s):  
A. S. Kao ◽  
H. A. Kuhn ◽  
O. Richmond ◽  
W. A. Spitzig
Keyword(s):  
High Pressure ◽  
Hydrostatic Pressure ◽  
Fracture Surface ◽  
Atmospheric Pressure ◽  
Fracture Mechanism ◽  
Shear Crack ◽  
Applied Pressure ◽  
Void Formation ◽  
Tensile Fracture ◽  
Central Crack

Void formation in tensile test under hydrostatic pressure is characterized through quantitative metallography, and the fracture mechanism under pressure is analyzed by fractography. Transition of the fracture surface from the cup-and-cone under atmospheric pressure to a slant structure under high pressure is explained on the basis of the void development leading to fracture and the concomitant change in fracture mechanism. The concept of “shear blocks” is introduced to illustrate the features observed on the fracture surface of specimens tested under high pressure. It is postulated that shear blocks evolve to connect the central crack regions with the shear crack initiated on neck surface due to the severe necking deformation under applied pressure.

The Rosette, Star, Tensile Fracture

1968 ◽  
Vol 90 (1) ◽  
pp. 21-27 ◽  
Author(s):  
W. R. Clough ◽  
R. M. Vennett ◽  
R. J. Hrubec
Keyword(s):  
Electron Microscope ◽  
Tensile Testing ◽  
Tensile Fracture ◽  
Fracture Modes ◽  
Fracture Topography ◽  
Fracture Configuration ◽  
Temperature Ranges ◽  
Fracture Theory ◽  
Quenched And Tempered Steel ◽  
Tempered Steel

A type of tensile fracture topography encountered fairly often in certain temperature ranges with specimens from forgings, billets, rod, and bar of quenched and tempered steel, is the “star” or “rosette.” Having available several steels which had been shown to be capable of exhibiting the rosette, star, fracture, tensile testing was done to establish the temperature ranges for which this fracture configuration was applicable. Explanations of the fracture, and determinations of the fracture modes, were sought through experimentation involving metallography and the electron microscope, and by application of continuum mathematical plasticity-fracture theory.

Study on Forming Mechanism of Lamination Defect of AH36 Shipbuilding Plate Steel

2012 ◽  
Vol 562-564 ◽  
pp. 106-110 ◽  
Author(s):  
Rui Feng ◽  
Rui Tang Zhang ◽  
Sheng Li Li ◽  
Guan Hong Kong ◽  
Xin De Zhu
Keyword(s):  
Steel Plate ◽  
Solidification Process ◽  
Tensile Fracture ◽  
Surface Zone ◽  
Plate Steel ◽  
Forming Mechanism ◽  
Deformation Stage ◽  
Continuous Casting Slab ◽  
Transmission Electron ◽  
Deformation And Fracture

The lamination defect makes the mechanical properties deterioration along the thickness of steel plate and therefore finding out the forming mechanism is of great significance for production of shipbuilding plate steel. The tensile fracture and microstructure characteristics on AH36 shipbuilding plate steel of lamination defect were studied with Scanning Electron Microscope (SEM), Transmission Electron Microscopy (TEM), etc. The results show that the strength-toughness properties vary widely at different thickness of the steel plate due to different ferrite grain size, and the center zone firstly yields and steps into plastic deformation stage due to coarse ferrite grain subjected to tensile stress, while the surface zone is still in elastic deformation stage due to relatively fine ferrite grain. The inconsistency of deformation and fracture leads to fracture separation, namely lamination. The continuous banded Widmanstätten structure, strip-shaped sulphide inclusions and mixed ferrite grain distributed at the center of shipbuilding plate steel create conditions for the lamination defect, which are important reasons for fracture separation. Widmanstätten structure at the center of steel plate has relationship with coarse austenite grain, and strip-shaped sulphide inclusions have relationship with centerline segregation of continuous casting slab during solidification process.

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