Elastomer-Gasoline Blends Interactions I. Effects of Methanol-Gasoline Mixtures on Elastomers

1983 ◽  
Vol 56 (1) ◽  
pp. 135-168 ◽  
Author(s):  
Ismat A. Abu-Isa

Abstract 1. Properties of most fuel resistant elastomers are degraded to a larger extent by mixtures of methanol and gasoline than by the pure components. 2. The data on all elastomers except the fluorocarbon can be explained in terms of the solubility parameter concept. 3. The ultimate tensile strength and ultimate elongation of swelled elastomer networks are quantitatively related to volume swell by simple linear relationships. 4. Ultimate stress and ultimate elongation of swelled elastomer networks obey equilibrium stress-strain relationships.

1961 ◽  
Vol 34 (3) ◽  
pp. 897-909
Author(s):  
Thor L. Smith ◽  
Paul J. Stedry

Abstract A study was made previously of the temperature and strain rate dependence of the stress at break (tensile strength) and the ultimate elongation of an unfilled SBR rubber. In that study, stress-strain curves to the point of rupture were measured with an Instron tensile tester on ring type specimens at 14 temperatures between −67.8° and 93.3° C, and at 11 strain rates between 0.158×10−3 and 0.158 sec−1 at most temperatures. The tensile strength was found to increase with both increasing strain rate and decreasing temperature. At all temperatures above −34.4° C, the ultimate elongation was likewise found to increase with increasing strain rate and decreasing temperature but at lower temperatures the opposite dependence on rate was observed; at −34.4° C, the ultimate elongation passed through a maximum with increasing rate.


Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3936
Author(s):  
Langni Deng ◽  
Lizhen Lei ◽  
Shijin Lai ◽  
Ling Liao ◽  
Zheng Zhou

The axial tensile properties of FRP mesh-reinforced ECC composites (TRE) were investigated experimentally under the consideration of four influencing factors: grid type, number of reinforcement layers, ECC matrix thickness, and sticky sand treatment on the grid surface. The test results showed that the axial stiffness and tensile strength of the composite were significantly increased, and the tensile properties were significantly improved under the effect of FRP grid reinforcement. Increasing the thickness of the ECC matrix can obviously improve the crack resistance of composites. The ultimate tensile strength of FRP lattice-reinforced ECC composites increased significantly with the increase in the number of lattice layers, but had no significant effect on the crack resistance. The tensile properties of CFRP grid-reinforced ECC composites were slightly better compared to BFRP grid-reinforced ECC composites. The crack resistance and ultimate tensile strength of the composites were slightly improved by impregnating the surface of the FRP grid with adhesive-bonded sand treatment. Based on the experimental data, the tensile stress–strain constitutive model of FRP grid-reinforced ECC composites is established. The calculation results show that the theoretical values of the model agree well with the experimental values. Therefore, it can be used to reflect the stress–strain change state of FRP lattice-reinforced ECC composites during axial tension.


Author(s):  
Liyang Huang ◽  
Jiru Zhong ◽  
Guoyao Chen ◽  
Tong Xu ◽  
Kaishu Guan

The instrumented indentation test (IIT) is an attractive non-destructive testing technique. Determining accurate strength properties of steel using IIT is still challenging. In this paper, a new methodology is proposed to acquire the yield and ultimate tensile strength from a single IIT. This method extracts true stress-strain curves from IIT results. Acquired stress-strain curves indicate that the initial yield stress is not repeatable. This is caused by the inhomogeneous deformation of IIT specimens. Based on the obtained true stress-stain curves, corresponding yield strength, and ultimate tensile strength are calculated through theoretical derivation. The results show that the strength has a convergent tendency. On basis of this phenomenon, the strength is determined with an extrapolating method. Finally, the strength properties of Q345R are investigated to verify the reliability of this method. It is found that the strength determined from IIT and conventional tensile tests shows good agreement. The proposed method is effective in predicting strength properties from a single instrumented indentation test.


Metals ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 69
Author(s):  
Michela Simoncini ◽  
Antonio Costa ◽  
Sergio Fichera ◽  
Archimede Forcellese

Friction stir welding (FSW) is a well-established welding technique, which allows joining abutting surfaces by generating heating through a rotating and translating tool specifically shaped. Differently from the conventional techniques, continuous welding processes can be executed by FSW, thus supporting the economy of scales objectives. This paper deals with the selection of the optimal process parameters for the FSW of the AA6082 aluminum alloy. Three welding parameters, namely tool plunging, rotational speed and welding speed, have been handled as independent variables for developing two mathematical models by means of a non-linear regression-based approach, with the aim of predicting both ultimate tensile strength and ultimate elongation of the welded joints. A set of additional experimental tests has been used to validate the mentioned metamodels and finally three different metaheuristic algorithms have been implemented for selecting the best process parameters able to maximize the aforementioned mechanical properties. A comparison analysis based on further experimental tests confirmed the accuracy of the predicting metamodels and the quality of solutions yielded by the proposed optimization approaches.


2019 ◽  
Vol 13 (4) ◽  
pp. 5804-5817
Author(s):  
Ibrahim Sabry

It is expected that the demand for Metal Matrix Composite (MMCs) will increase in these applications in the aerospace and automotive industries sectors, strengthened AMC has different advantages over monolithic aluminium alloy as it has characteristics between matrix metal and reinforcement particles.  However, adequate joining technique, which is important for structural materials, has not been established for (MMCs) yet. Conventional fusion welding is difficult because of the irregular redistribution or reinforcement particles.  Also, the reaction between reinforcement particles and aluminium matrix as weld defects such as porosity in the fusion zone make fusion welding more difficult. The aim of this work was to show friction stir welding (FSW) feasibility for entering Al 6061/5 to Al 6061/18 wt. % SiCp composites has been produced by using stir casting technique. SiCp is added as reinforcement in to Aluminium alloy (Al 6061) for preparing metal matrix composite. This method is less expensive and very effective. Different rotational speeds,1000 and 1800 rpm and traverse speed 10 mm \ min was examined. Specimen composite plates having thick 10 mm were FS welded successfully. A high-speed steel (HSS) cylindrical instrument with conical pin form was used for FSW. The outcome revealed that the ultimate tensile strength of the welded joint (Al 6061/18 wt. %) was 195 MPa at rotation speed 1800 rpm, the outcome revealed that the ultimate tensile strength of the welded joint (Al 6061/18 wt.%) was 165 MPa at rotation speed 1000 rpm, that was very near to the composite matrix as-cast strength. The research of microstructure showed the reason for increased joint strength and microhardness. The microstructural study showed the reason (4 %) for higher joint strength and microhardness.  due to Significant   of SiCp close to the boundary of the dynamically recrystallized and thermo mechanically affected zone (TMAZ) was observed through rotation speed 1800 rpm. The friction stir welded ultimate tensile strength Decreases as the volume fraction increases of SiCp (18 wt.%).


Alloy Digest ◽  
1997 ◽  
Vol 46 (10) ◽  

Abstract Vasco 9-4-20 (0.20 wt% C) is a premium quality aircraft steel that combines high tensile strength with good fracture toughness. It is a heat-treatable alloy capable of developing an ultimate tensile strength greater than 190 ksi. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fracture toughness. It also includes information on high temperature performance as well as heat treating, machining, and joining. Filing Code: SA-489. Producer or source: Vasco, An Allegheny Teledyne Company.


2020 ◽  
Vol 17 (6) ◽  
pp. 831-836
Author(s):  
M. Vykunta Rao ◽  
Srinivasa Rao P. ◽  
B. Surendra Babu

Purpose Vibratory weld conditioning parameters have a great influence on the improvement of mechanical properties of weld connections. The purpose of this paper is to understand the influence of vibratory weld conditioning on the mechanical and microstructural characterization of aluminum 5052 alloy weldments. An attempt is made to understand the effect of the vibratory tungsten inert gas (TIG) welding process parameters on the hardness, ultimate tensile strength and microstructure of Al 5052-H32 alloy weldments. Design/methodology/approach Aluminum 5052 H32 specimens are welded at different combinations of vibromotor voltage inputs and time of vibrations. Voltage input is varied from 50 to 230 V at an interval of 10 V. At each voltage input to the vibromotor, there are three levels of time of vibration, i.e. 80, 90 and 100 s. The vibratory TIG-welded specimens are tested for their mechanical and microstructural properties. Findings The results indicate that the mechanical properties of aluminum alloy weld connections improved by increasing voltage input up to 160 V. Also, it has been observed that by increasing vibromotor voltage input beyond 160 V, mechanical properties were reduced significantly. It is also found that vibration time has less influence on the mechanical properties of weld connections. Improvement in hardness and ultimate tensile strength of vibratory welded joints is 16 and 14%, respectively, when compared without vibration, i.e. normal weld conditions. Average grain size is measured as per ASTM E 112–96. Average grain size is in the case of 0, 120, 160 and 230 is 20.709, 17.99, 16.57 and 20.8086 µm, respectively. Originality/value Novel vibratory TIG welded joints are prepared. Mechanical and micro-structural properties are tested.


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