Assessment of Mechanical Properties of Cold Formed Steel Material at Elevated Temperature

2016 ◽  
Vol 846 ◽  
pp. 27-36
Author(s):  
Fadhluhartini Muftah ◽  
Mohd Syahrul Hisyam Mohd Sani ◽  
Ahmad Rasidi Osman ◽  
Mohd Azran Razlan ◽  
Shahrin Mohammad
Keyword(s):  
Elastic Modulus ◽  
Elevated Temperature ◽  
Ambient Temperature ◽  
Yield Stress ◽  
Material Properties ◽  
High Efficiency ◽  
Strain Curve ◽  
Ultimate Stress ◽  
Fire Incident ◽  
Cold Formed Steel

Fire accident is considered as the one of most severe environmental hazards to building and infrastructure. Cold formed steel (CFS) beam has been used extensively as primary load bearing structural member in many applications in the building construction due to high efficiency in term of production, fabrication, and assembling in construction. This material must be well perform in fire incident in term of its integrity and stability of structural for a period of time. Hence, the assessment of the material properties of this material is greatly important in order to predict the performance of this structure under fire incident. The tensile coupon tests of CFS are according to BS EN 10002-1:2001. The CFS material G450 with 1.9 mm thickness is used in this study. The elastic modulus, yield stress, correspondent percentage strain at yield stress, ultimate stress, and correspondent percentage strain of ultimate stress was 200.3 GPa, 540.5 MPa, 0.478 %, 618.8 MPa, and 8.701 % respectively. The results of the ambient temperature test have been used to assess the mechanical strength of CFS at elevated temperature. The discussion of material properties is based on EC3-1-2 and proposed model from other researchers. The main material properties discussed is the stress-strain curve, elastic modulus, yield strength at elevated temperature was determined. The actual elastic region is slightly lower than the prediction of EC3-1.2 at ambient temperature, but well fit with two other studies. Besides that, the actual material properties experience strain hardening after yielding and reach a maximum stress up to 618 MPa while EC3-1.2 predict the constant value of the yield stress after yield until 15 % strain,other two study was fit the ambient tensile test up to ultimate stress, and fit until 2 % strain level.

scholarly journals Mechanical Properties of Steels for Cold-Formed Steel Structures at Elevated Temperatures

2020 ◽  
Vol 2020 ◽  
pp. 1-18
Author(s):  
Zhen Nie ◽  
Yuanqi Li ◽  
Yehua Wang
Keyword(s):  
Mechanical Properties ◽  
Material Properties ◽  
Elevated Temperatures ◽  
Elasticity Modulus ◽  
Mechanical Performance ◽  
Strain Curve ◽  
Steel Structures ◽  
Test Method ◽  
Stress Relieving ◽  
Cold Formed Steel

It is highly important to clarify the high-temperature mechanical properties in the design of cold-formed steel (CFS) structures under fire conditions due to the unique deterioration feature in material properties under fire environment and associated reduction to the mechanical performance of members. This paper presents the mechanical properties of widely used steels for cold-formed steel structures at elevated temperatures. The coupons were extracted from original coils of proposed full annealed steels (S350 and S420, with nominal yielding strengths 280 MPa and 350 MPa) and proposed stress relieving annealed steels (G500, with nominal yielding strength 500 MPa) for CFS structures with thickness of 1.0 mm and 1.2 mm, and a total of nearly 50 tensile tests were carried out by steady-state test method for temperatures ranging from 20 to 700°C. Based on the tests, material properties including the yield strengths, ultimate strengths, the elasticity modulus, and the stress-strain curve were obtained. Meanwhile, the ductility of steels for CFS structures was discussed. Then, the temperature-dependent retention factors of yield strengths and elasticity modulus were compared to those provided by design codes and former researchers. Finally, a set of prediction equations of the mechanical properties for steels for CFS structures at elevated temperatures was proposed depending on existing tests data.

scholarly journals Mechanical characterization of polylactic acid, polycaprolactone and Lay-Fomm 40 parts manufactured by fused deposition modeling, as a function of the printing parameters

2019 ◽  
Vol 16 (2) ◽  
pp. 25-31 ◽  
Author(s):  
Jessica Zuleima Parrado-Agudelo ◽  
Carlos Narváez-Tovar
Keyword(s):  
Mechanical Properties ◽  
Elastic Modulus ◽  
Yield Stress ◽  
Fused Deposition Modeling ◽  
Material Selection ◽  
Ultimate Tensile Stress ◽  
Ultimate Stress ◽  
Fused Deposition ◽  
Raster Angle ◽  
Printing Parameters

This study aims to determine the mechanical properties of parts manufactured by Fused Deposition Modeling (FDM) using three biocompatible polymer materials: Polylactic Acid (PLA), Polycaprolactone (PCL) and Lay-Fomm 40. Also, it was analyzed the influence of different printing parameters, material selection, infill percentage, and raster angle, over the mechanical properties. The samples were subjected to tension and compression tests using a universal testing machine, and elastic modulus, yield stress, and ultimate stress were obtained from the stress-strain curves. PLA samples have the highest elastic modulus, yield stress and ultimate stress for both compression and tension tests, for example, the ultimate tensile stress with infill percentage of 30 % and raster angle of 0-90° has an average value of 41.20 MPa, while PCL samples had an ultimate tensile stress average value of 9.68 MPa. On the other hand, Lay-Fomm40 samples had the highest elongations, with percentage values between 300 and 600 %. Finally, ANOVA analysis showed that the choice of the material is the leading printing parameter that contributes to the mechanical properties, with percentages of 84.20% to elastic modulus, 93.30% to yield stress, and 82.44% to ultimate stress. The second important factor is the raster angle, with higher strengths for the 0-90° when compared to 45-135°. On the other hand, the contribution of the infill percentage to the mechanical properties was no statistically significant. The obtained results could be useful for material selection and 3D printing parameters definition for additive manufacturing of scaffolds, implants, and other structures for biomedical and tissue engineering applications.

scholarly journals Study on Tensile Properties of CFRP Plates under Elevated Temperature Exposure

Materials ◽  
2019 ◽  
Vol 12 (12) ◽  
pp. 1995 ◽  
Author(s):  
Yongxin Yang ◽  
Yanju Jiang ◽  
Hongjun Liang ◽  
Xiaosan Yin ◽  
Yue Huang
Keyword(s):  
Tensile Strength ◽  
Elastic Modulus ◽  
Elevated Temperature ◽  
Tensile Properties ◽  
Failure Mode ◽  
Elevated Temperatures ◽  
Strain Curve ◽  
Effect Of Temperature ◽  
Temperature Exposure ◽  
The Impact

Elevated temperature exposure has a negative effect on the performance of the matrix resin in Carbon Fiber Reinforced Plastics (CFRP) plates, whereas limited quantitative research focuses on the deteriorations. Therefore, 30 CFRP specimens were designed and tested under elevated temperatures (10, 30, 50, 70, and 90 °C) to explore the degradations in tensile properties. The effect of temperature on the failure mode, stress-strain curve, tensile strength, elastic modulus and elongation of CFRP plates were investigated. The results showed that elevated temperature exposure significantly changed the failure characteristics. When the exposed temperature increased from 10 °C to 90 °C, the failure mode changed from the global factures in the whole CFRP plate to the successive fractures in carbon fibers. Moreover, with temperatures increasing, tensile strength and elongation of CFRP plates decreases gradually while the elastic modulus shows negligible change. Finally, the results of One-Way Analysis of Variance (ANOVA) show that the degradation of the tensile strength of CFRP plates was due to the impact of elevated temperature exposure, rather than the test error.

scholarly journals Fundamentals of cutting

2016 ◽  
Vol 6 (3) ◽  
pp. 20150108 ◽  
Author(s):  
J. G. Williams ◽  
Y. Patel
Keyword(s):  
Fracture Toughness ◽  
Elastic Modulus ◽  
Fracture Mechanics ◽  
Yield Stress ◽  
Material Properties ◽  
Orthogonal Cutting ◽  
Wedge Angle ◽  
Tool Geometry ◽  
Plastic Shear ◽  
Plastic Bending

The process of cutting is analysed in fracture mechanics terms with a view to quantifying the various parameters involved. The model used is that of orthogonal cutting with a wedge removing a layer of material or chip. The behaviour of the chip is governed by its thickness and for large radii of curvature the chip is elastic and smooth cutting occurs. For smaller thicknesses, there is a transition, first to plastic bending and then to plastic shear for small thicknesses and smooth chips are formed. The governing parameters are tool geometry, which is principally the wedge angle, and the material properties of elastic modulus, yield stress and fracture toughness. Friction can also be important. It is demonstrated that the cutting process may be quantified via these parameters, which could be useful in the study of cutting in biology.

scholarly journals Elevated temperature material properties of cold-formed steel hollow sections

2015 ◽  
Vol 90 ◽  
pp. 84-94 ◽  
Author(s):  
Finian McCann ◽  
Leroy Gardner ◽  
Sophie Kirk
Keyword(s):  
Elevated Temperature ◽  
Material Properties ◽  
Cold Formed Steel

Experimental Investigations of the Effects of Multiple Heat Straightening Repair on the Structural Properties of Bridge Steels

2005 ◽  
Vol 1907 (1) ◽  
pp. 67-77
Author(s):  
Keith Kowalkowski ◽  
Amit H. Varma
Keyword(s):  
Fracture Toughness ◽  
Elastic Modulus ◽  
Yield Stress ◽  
Structural Properties ◽  
Surface Hardness ◽  
Ultimate Stress ◽  
Experimental Investigations ◽  
Percent Elongation ◽  
Damage Repair ◽  
Heat Straightening

The effects of multiple damage-heat straightening repair cycles (i.e., multiple cycles of damage followed by heat straightening repair) on the fundamental structural properties of typical bridge steels ASTM A36, A588, and A7 were evaluated. The damage and repair parameters considered in the study are the damage strain (ed), the restraining stress (sr), and the number of multiple damage-repair cycles (Nr). The effects of these parameters on the following structural properties were evaluated: elastic modulus, yield stress, ultimate stress, percent elongation, surface hardness, and fracture toughness. Seventy-five laboratory-scale specimens made from A36, A588, or A7 steel were subjected to multiple damage-repair cycles, and their effects on the structural properties were evaluated. The results indicate that multiple damage-repair cycles have a small influence (±15%) on the elastic modulus, yield stress, and ultimate stress. However, the percent elongation and fracture toughness of the damaged-repaired steel are influenced significantly. On the basis of reductions in the percent elongation and fracture toughness, it is recommended that A7 and A36 steel be limited to three damage-heat straightening repair cycles. A588 steel can be subjected to five damage-heat straightening repair cycles.

An elastic-plastic indentation model and its solutions

1996 ◽  
Vol 11 (9) ◽  
pp. 2358-2367 ◽  
Author(s):  
Weiping Yu ◽  
James P. Blanchard
Keyword(s):  
Experimental Data ◽  
Mechanical Properties ◽  
Elastic Modulus ◽  
Yield Stress ◽  
Material Properties ◽  
Hardness Test ◽  
Plastic Materials ◽  
Indentation Tests ◽  
Plastic Indentation ◽  
Comparison With Experimental Data

An analytical model of hardness has been developed. Four major indentation tests, namely indentation by cones, wedges, spheres, and flat-ended, axisymmetric cylinders have been analyzed based on the model. Analytical relationships among hardness, yield stress, elastic modulus, Poisson's ratio, and indenter geometries have been found. These results enable hardness to be calculated in terms of uniaxial material properties and indenter geometries for a wide variety of elastic and plastic materials. These relationships can also be used for evaluating other mechanical properties through hardness measurements and for converting hardness from one type of hardness test into those of a different test. Comparison with experimental data and numerical calculations is excellent.

Stress Analysis and Sealing Performance Evaluation of Pipe Flange Connection at Elevated Temperature

2008 ◽  
Author(s):  
Yoshio Takagi ◽  
Hiroyasu Torii ◽  
Toshiyuki Sawa ◽  
Naoki Kawasaki
Keyword(s):  
Thermal Expansion ◽  
Elevated Temperature ◽  
Thermal Expansion Coefficient ◽  
Expansion Coefficient ◽  
Material Properties ◽  
Strain Curve ◽  
Flange Connection ◽  
Sealing Performance ◽  
Higher Temperature ◽  
Experimental Difficulty

Although a lot of pipe flange connections are exposed to elevated temperature during plant operation, a sealing performance of the pipe flange connections at elevated temperature is not well understood because of the experimental difficulty and the analytical problems due to the lack of the materials properties of gaskets at elevated temperature. The authors have been evaluating the sealing performance of the pipe flange connections at elevated temperature with numerical and experimental analysis and showed the strong effect of the material properties of the gaskets, like a thermal expansion coefficient and a stress-strain curve, on the sealing performance. In order to make a further evaluation, the effect of material properties on the sealing performance was analyzed by using FEM. In the FE analysis, the material properties were varied to evaluate the effect of them on the sealing performance. Furthermore, the material properties and the mechanical characteristic of the gasket were evaluated as a function of temperature. The obtained properties were used to reanalyze the sealing performance of the pipe flange connection. As a result, the gasket stress induced by the mismatch of the thermal expansion between the gasket and flange/bolt increased as increasing the temperature in the case that the thermal expansion coefficient of the gasket was larger than that of bolt/flange material and the sealing performance of the pipe flange connection was improved. However, the improvement in the sealing performance at elevated temperature was not expected so much at higher temperature due to the less increment of the thermal expansion and thermal stress of the gasket. This paper discuss about the change in the sealing performance of the pipe flange connection under elevated temperature considering the material properties and mechanical characteristics of the gasket.

scholarly journals Shear modulus and yield stress of foams: contribution of interfacial elasticity

Soft Matter ◽  
2021 ◽  
Vol 17 (14) ◽  
pp. 3937-3944
Author(s):  
Annika R. Völp ◽  
Norbert Willenbacher
Keyword(s):  
Elastic Modulus ◽  
Block Copolymer ◽  
Shear Modulus ◽  
Yield Stress ◽  
Protein Food ◽  
General Correlation

A general correlation of foam shear modulus G0 and yield stress τy with the interfacial elastic modulus of foaming solutions in shear and dilation E∞ was found for surfactant, block-copolymer, protein, food, and particle-stabilized foams.

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