Application of small specimen testing technique for mechanical property assessment of discontinuously reinforced composites
01 Jan 2006-Materials Science and Technology (Taylor & Francis)-Vol. 22, Iss: 1, pp 61-71
TL;DR: In this paper, the applicability of a laboratory shear punch testing system, which was fabricated to evaluate the mechanical properties of different materials (steels, aluminium alloys, copper alloy, titanium alloys and cobalt alloys), was extended to include tensile mechanical property assessment of discontinuously reinforced metal matrix composites.
Abstract: The shear punch experiment is a small specimen testing technique that has been used to assess the flow properties, such as strength and ductility, of traditional engineering alloys when material availability is limited. In the present study, the applicability of a laboratory shear punch testing system, which was fabricated to evaluate the mechanical properties of different materials (steels, aluminium alloys, copper alloys, titanium alloys and cobalt alloys), was extended to include tensile mechanical property assessment of discontinuously reinforced metal matrix composites. In employing this testing technique to discontinuously reinforced composites, the shear punch load–displacement data were examined to identify the critical regions of the flow curve, i.e. elasticity followed by yielding, work hardening, ultimate tensile strength and fracture. The load–displacement curves and the fracture characteristics generated by shear punch testing were then compared with the conventional tensile data and ...
TL;DR: In this paper, an electron beam (EB) was welded as part of a study to determine the influence of parametric conditions on the characteristics of the weldment to optimize the joining process.
TL;DR: In this article, the deformation behavior of AISI 1015 low-carbon steel and stainless steel sheets was investigated by uniaxial tension and the shear punch test (SPT).
Abstract: The deformation behavior of AISI 1015 low-carbon steel, and AISI 304 stainless steel sheets was investigated by uniaxial tension and the shear punch test (SPT). Both materials were cold rolled to an 80% thickness reduction and subsequently annealed in the temperature range 25-850 °C to produce a wide range of yield and ultimate strength levels. The correlations between shear punch and tensile yield and ultimate stresses were established empirically. Different linear relationships having different slopes and intercepts were found for the low-carbon and stainless steel sheets, and the possible parameters affecting the correlation were discussed. It was shown that, within limits, yield and tensile strength of thin steel sheets can be predicted from the shear data obtained by the easy-to-perform SPT.
22 Jul 2020-Materials Science and Engineering A-structural Materials Properties Microstructure and Processing
TL;DR: In this article, the evolutions of microstructure and mechanical properties during shear punch testing (SPT) of an AISI 304L metastable austenitic stainless steel were studied at deformation temperatures ranging from 0°C to 550 °C and strain rates in the range of 10-3 s-1 to 1 s -1.
Abstract: The evolutions of microstructure and mechanical properties during shear punch testing (SPT) of an AISI 304L metastable austenitic stainless steel were studied at deformation temperatures ranging from 0 °C to 550 °C and strain rates in the range of 10-3 s-1 to 1 s-1. Based on the X-ray diffraction (XRD) phase analysis and metallographic observations, it was inferred that by increasing the deformation temperature from 0 °C to 200 °C, the amount of transformed strain-induced martensite decreases at all strain rates, leading to the weakening of the transformation-induced plasticity (TRIP) effect. However, depending on the strain rate, at temperatures higher than 200 °C, an anomalous trend in shear strength was observed, i.e. the shear strength rose by increasing the deformation temperature at low strain rates, due to the dynamic strain aging (DSA) phenomenon. Strain rate sensitivity studies in conjunction with the microstructural evolutions revealed four temperature-dependent regimes: 0–200 °C, 200–300 °C, 300–500 °C and higher than 500 °C, where the respective strain rate sensitivity index (m) becomes positive, zero, negative, and then positive again. These regimes were rationalized based on the TRIP effect, DSA phenomenon, and thermally-activated dislocation glide.
13 Jan 2017-Materials Science and Engineering A-structural Materials Properties Microstructure and Processing
TL;DR: In this article, small-scale shear punch testing has been applied to a butt joint created by friction stir welding of two adjoining AA2139-T8 plates, where a series of 144 shear punching tests were carried out in a 12×12 grid pattern on the retreating half of the weld.
Abstract: Small-scale shear punch testing has been applied to a butt joint created by friction stir welding of two adjoining AA2139-T8 plates. Advantages of this technique include the ability to perform a large number of independent tests on a given volume of material and the ability to measure site-specific differences and variations in local material properties. As such, combined with a simultaneous evaluation of the weld morphology, a series of 144 shear punch tests were carried out in a 12×12 grid pattern on the retreating half of the weld. The overlay of the grid pattern onto the etched surface allowed a correlation of the microstructure and mechanical properties measured across the weld at each shear punch site. Two-dimensional color enhanced property maps were generated to provide a powerful site specific visualization of the unique or distinctive microstructural features and how they correlate with the local mechanical response across the weld. One of the more insightful discoveries was the weld nugget region undergoing 2.5 times more strain-hardening than the base plate material, while simultaneously experiencing the Portevin-LeChatelier effect. Aspects of the technique and results of our experiments are described.
TL;DR: In this paper, the tensile test and shear punch test (SPT) was used for characterizing the mechanical properties of green ceria-doped ceria (Ce0.9Gd0.1O1.95, 10GDC) tapes.
Abstract: Mechanical properties of gadolinium-doped ceria (Ce0.9Gd0.1O1.95, 10GDC) green tape prepared by aqueous-based tape casting process were characterized by tensile test and shear punch test (SPT). SPT was found to be a useful method for characterizing mechanical properties of green tapes. Microstructures and mechanical properties such as flexural modulus, bending strength, and microhardness of tapes sintered at 1,300–1,500 °C have been evaluated. Indentation fracture toughness was also determined by the method of Palmqvist cracks at different applied loads for tapes sintered at 1,500 °C. Grain size measurements showed that excessive grain growth occurred during sintering despite using 10GDC nanopowders as the starting material. However, mechanical properties of sintered tapes improved by increasing sintering temperature and the results are comparable with those reported for 10GDC in literature.
25 Mar 2005-Materials Science and Engineering A-structural Materials Properties Microstructure and Processing
TL;DR: In this paper, a linear correlation between the shear data and tensile data was established for yield and ultimate tensile strength for different materials; mild steel, pure Al, Zn, brass (Cu-30% Zn by wt.), Al 6061, Austenitic and Martensitic stainless steels were evaluated.
Abstract: The evaluation of mechanical properties like yield and ultimate tensile strengths from shear–punch tests is important when the availability of material is limited. A shear–punch test setup was built in our laboratory and the mechanical properties for different materials; mild steel, pure Al, Zn, brass (Cu–30% Zn by wt.), Al 6061, Austenitic and Martensitic stainless steels were evaluated. A new method using 1% offset criterion in conjunction with normalized shear–punch curves was used to measure the shear yield strength. A linear correlation between the shear data and tensile data was established for yield and ultimate strengths. The variation of the yield and ultimate shear strength was studied as a function of the sample thickness and die–punch clearance for soft, medium and high strength materials.
TL;DR: A wide array of specimen geometries and test techniques have now been developed as discussed by the authors, and the purpose of this paper is to review these techniques and examine their status, problems, and potential for future applications.
Abstract: Small specimen test technology has evolved out of the necessity to develop and monitor materials proposed for or used in nuclear power generation systems. Development of materials for improved cladding and in-core structures for fission reactors and assessment of core materials and pressure vessel steels already under irradiation necessitated the use of specimens which fit into existing irradiation space or which could be extracted from irradiated structures, such as cladding or ducts. Interest in simulating neutron irradiation by light and heavy ion irradiation led to the development of thin foil and wire geometry specimens. Further, interest in developing materials for fusion reactors has added additional constraints on specimen sizes associated with available irradiation volumes in existing and proposed high-energy neutron irradiation facilities. Consequently, a wide array of specimen geometries and test techniques has now been developed. It is the purpose of this paper to review these techniques and examine their status, problems, and potential for future applications.
TL;DR: A variety of microhardness, bulge, shear punch, indentation creep and load relaxation tests for obtaining strength, ductility, time-dependent flow, and fracture behavior information on specimens as small as TEM discs are under development at the University of California, Santa Barbara as discussed by the authors.
TL;DR: In this article, an expression for the maximum in punch force caused by plastic instability and the initiation and propagation of cracks after the onset of plastic flow was derived in terms of work hardening index of the workpiece, its thickness and state of prestrain.
TL;DR: The ductility of the TiC composite is about 2 pct at room temperature and increases with an increase of temperature as mentioned in this paper, but some ductility is observed at higher temperatures.
Abstract: Samples of Ti-6A1-4V containing 10 vol pct of either TiC or SiC have been tested in tension at temperatures up to 760 °C, and the mechanical properties have been compared with those of the unreinforced matrix alloy. It has been found that the yield stress and the tensile strength of the TiC-containing composite are superior to those of the SiC composite at room temperature but that this behavior is reversed at the higher temperatures. The ductility of the TiC composite is about 2 pct at room temperature and increases with increase of temperature. No ductility is found for the SiC composite at room temperature, but some ductility is observed at the higher temperatures. These observations are interpreted in terms of the extent and nature of the reaction zones between the matrix alloy and the reinforcement and in terms of the failure mechanisms observed using scanning (SEM) and transmission electron microscopy (TEM).