Effect of Retrogression and Re-Aging Treatment on the Organization and Properties of Cast Aluminum Alloys

In this paper, Samples are subjected to tensile test, metallographic microscope observation, scanning electron microscopy (SEM) analysis for exploring the effect of different retrogression and re-aging (RRA) treatments on the organization and properties of casting aluminum alloy. Results show that after aging at 170°C for 10h ,then regression at 230°C for 10min ,finally aging at 170°C for 10h, tensile strength of the sample is 430.19MPa, elongation is 6.18%, compared with the sample aged at 170°C for 10h (The tensile strength was 426.78MPa, elongation was 3.68%). It demonstrated that through the RRA process, strength of sample can effectively maintain at a similar high level as the samples processed single-stage aging. Meanwhile, the elongation of the sample increase nearly 67.9%. The microstructure characterizations indicate that RRA treatment induced the formation and growth of rod-like T phase, and the T phase homogeneously dispersed in the matrix of alloy. This process is proposed to be the major reason for the improvement of ductility.

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The Effect of Aging on Precipitates, Mechanical and Magnetic Properties of Fe-21Cr-15Ni-6Mn-Nb Low Magnetic Stainless Steel

Metals ◽

10.3390/met11050819 ◽

2021 ◽

Vol 11 (5) ◽

pp. 819

Author(s):

Changsheng Li ◽

Kun Li ◽

Jingbo Dong ◽

Jinyi Ren ◽

Yanlei Song

Keyword(s):

Heat Treatment ◽

Tensile Strength ◽

Stainless Steel ◽

Magnetic Properties ◽

Solution Heat Treatment ◽

Aging Treatment ◽

Relative Magnetic Permeability ◽

Coarsening Behavior ◽

The Matrix ◽

Coherent Orientation

The effect of aging on the precipitates, mechanical and magnetic properties of Fe-21Cr-15Ni-6Mn-Nb low magnetic stainless steel were investigated. The steel was aged at 550–750 °C for 2 h after solution heat treatment at 1100 °C for 1 h. During the aging treatment, the (Nb, V)(C, N) particles gradually precipitated in the grain, which were coherent or semi-coherent with the matrix. When the aging temperature was beyond 650 °C, the coarsening rate of (Nb, V)(C, N) particles increase rapidly and the coherent orientation between (Nb, V)(C, N) particles and the matrix was lost gradually. Meanwhile, coarse M23C6 was distributed at the grain boundary with chain shape, which was non-coherent with the matrix. The coarsening behavior of (Nb, V)(C, N) precipitates in the grain was analyzed, and the size of the particles precipitated after aging treatment at 650°C for different time was calculated and studied. After aging treatment at 650 °C for 2 h, the yield strength and tensile strength of the stainless steel was 705.6 MPa and 1002.3 MPa, the elongation and the relative magnetic permeability was 37.8% and 1.0035, respectively.

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The Investigation on Aluminium Alloys Automobile Wheel with Low-Titanium Content Produced by Electrolysis

Materials Science Forum ◽

10.4028/www.scientific.net/msf.475-479.317 ◽

2005 ◽

Vol 475-479 ◽

pp. 317-320 ◽

Cited By ~ 1

Author(s):

Jing Pei Xie ◽

Ji Wen Li ◽

Zhong Xia Liu ◽

Ai Qin Wang ◽

Yong Gang Weng ◽

...

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Aluminium Alloys ◽

Solution Treatment ◽

A356 Alloy ◽

Aging Treatment ◽

Titanium Content ◽

The Matrix ◽

Automobile Wheel

The in-situ Ti alloying of aluminium alloys was fulfilled by electrolysis, and the material was made into A356 alloy and used in automobile wheels. The results show that the grains of the A356 alloy was refined and the second dendrites arm was shortened due to the in-situ Ti alloying. Trough 3-hour solution treatment and 2-hour aging treatment for the A356 alloy, the microstructures were homogeneous, and Si particles were spheroid and distribute in the matrix fully. The outstanding mechanical properties with tensile strength (σb≥300Mpa) and elongation values (δ≥10%) have been obtained because the heat treatment was optimized. Compared with the traditional materials, tensile strength and elongation were increased by 7.6~14.1% and 7.4~44.3% respectively. The qualities of the automobile wheels were improved remarkably.

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Mechanical Performance of a Cast A354 Aluminium Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.794-796.489 ◽

2014 ◽

Vol 794-796 ◽

pp. 489-494 ◽

Cited By ~ 2

Author(s):

J.H. Sandoval ◽

Adel M.A. Mohamed ◽

S. Valtierra ◽

F.H. Samuel

Keyword(s):

Tensile Properties ◽

Quality Index ◽

Mechanical Performance ◽

Cast Alloy ◽

Solution Treatment ◽

Aging Treatment ◽

Test Results ◽

Cast Aluminum ◽

Treatment Conditions ◽

Cast Aluminum Alloys

Cast aluminum alloys are an important group of materials which find wide application in the automotive industry. Insufficient studies have been carried out to date with regard to the mechanical performance of the aged A354 alloy. Therefore, the present work investigates the Quality index charts with the purpose of setting the limits of the tensile properties, as well as for comparing the mechanical behavior of cast alloy A354, to delineate the effect of the solution treatment applied. Tensile properties upon artificial aging in the temperature range of 155–350oC for times ranging from 2 to 100 hours are also investigated. The results showed that the use of quality index charts is a satisfactory method for presenting tensile test results and, for assessing the effect of solution and aging treatment conditions subjected to the modified and grain-refined A354 alloys. It is also observed that the quality index, Q, is more sensitive to variations in the tensile ductility than to tensile strength.

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Optimizing the Microstructure and Mechanical Properties of Vacuum Counter-Pressure Casting ZL114A Aluminum Alloy via Ultrasonic Treatment

Materials ◽

10.3390/ma13194232 ◽

2020 ◽

Vol 13 (19) ◽

pp. 4232

Author(s):

Gang Lu ◽

Pengpeng Huang ◽

Qingsong Yan ◽

Pian Xu ◽

Fei Pan ◽

...

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Aluminum Alloy ◽

Ultrasonic Treatment ◽

Eutectic Silicon ◽

Primary Phase ◽

Pressure Casting ◽

Counter Pressure ◽

Casting Aluminum Alloy ◽

Casting Aluminum

The effect of ultrasonic temperature on density, microstructure and mechanical properties of vacuum counter-pressure casting ZL114A alloy during solidification was investigated by optical microscopy (OM), scanning electron microscope (SEM) and a tensile test. The results show that compared with the traditional vacuum counter-pressure casting aluminum alloy, the primary phase and eutectic silicon of the alloy with ultrasonic treatment has been greatly refined due to the dendrites broken by ultrasonic vibration. However, the refining effect of ultrasonic treatment on vacuum counter-pressure casting aluminum alloy will be significantly affected by ultrasonic temperature. When the ultrasonic temperature increases from 680 °C to 720 °C, the primary phase is gradually refined, and the morphology of eutectic silicon also changes from coarse needle-like flakes to fine short rods. With a further increase in the ultrasonic temperature, the microstructure will coarse again. The tensile strength and elongation of vacuum counter-pressure casting ZL114A alloy increases first and then decreases with the increase of ultrasonic temperature. The optimal mechanical properties were achieved with tensile strength of 327 MPa and the elongation of 5.57% at ultrasonic temperature of 720 °C, which is 6.3% and 8.2%, respectively, higher than that of alloy without ultrasonic treatment.

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Effect Maleic Anhydride Polypropylene on Properties of Calcium Carbonate Filled Polypropylene/Ethylene Propylene Diene Terpolymer Composites

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.594-595.770 ◽

2013 ◽

Vol 594-595 ◽

pp. 770-774 ◽

Cited By ~ 1

Author(s):

Husseinsyah Salmah ◽

A. Siti Rohana ◽

Hussin Kamarudin

Keyword(s):

Tensile Strength ◽

Calcium Carbonate ◽

Maleic Anhydride ◽

Modulus Of Elasticity ◽

Sem Analysis ◽

Inorganic Filler ◽

Elongation At Break ◽

Ethylene Propylene ◽

The Matrix ◽

Ethylene Propylene Diene Terpolymer

Inorganic filler, calcium carbonate (CaCO3) was used as filler in the polypropylene (PP)/ ethylene propylene diene terpolymer (EPDM) composites. The composites were compatibilized with Maleic anhydride grafted polypropylene (MAPP) in order to improve the properties. The addition of CaCO3 at has increased the modulus of elasticity of composites but tensile strength and elongation at break of uncompatibilized composites decreased with increasing CaCO3. The result shows that the compatibilized composites higher tensile strength and Modulus of elasticity but lower elongation at break compared to uncompatibilized composites. At 10 wt% CaCO3 showed higher tensile strength of uncompatibiled and compatibilized composites. The morphology study from SEM analysis reveals that compatibilized composites show better interfacial adhesion between the filler and the matrix. The addition of MAPP has improved crystallinity of compatibilized composites.

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Effect of Heat Treatment on the Microstructure and Property of Al-Si-Mg Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.850.768 ◽

2016 ◽

Vol 850 ◽

pp. 768-772 ◽

Cited By ~ 1

Author(s):

Liu Yi Guan ◽

Bo Long Li ◽

Peng Qi ◽

Li Jun Wei ◽

Zuo Ren Nie

Keyword(s):

Heat Treatment ◽

Tensile Strength ◽

Brittle Fracture ◽

Solution Treatment ◽

Aging Treatment ◽

Mg Alloy ◽

Metallographic Analysis ◽

Air Cooling ◽

The Matrix ◽

Eutectic Si

The as-casted Al-Si-Mg alloy was treated by solution and aging process of 545°C/10h/water cooling plus 175°C/6h /air cooling. The effect of heat treatment on the microstructure and mechanical property of Al-Si-Mg was investigated by metallographic analysis, scanning electron microscopy, energy dispersion spectrum analysis and mechanical testing. The experimental results showed that the alloy had the ultimate tensile strength (UTS) of 317MPa and the elongation of 2%, and suitable for squeezing cast. During solution treatment, the plate-like eutectic Si particles became small granular or short bacilliform morphology, and the non-uniformly distributed eutectic phase was eliminated substantially. In addition, Si particles distributed uniformly and finely in the matrix. The tensile strength of as-casted alloy was 180 MPa, while it was up to 317 MPa after solution and aging treatment process, and the elongation increased from 2% to 3%, which is consistent with the microstructure. Fracture surface analysis showed that fracture mode of the alloy transformed from brittle fracture into co-existence of ductile fracture and brittle fracture during T6 treatment.

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Effect of the Eutectic Phase on the Microstructure and Tensile Strength of an Al–Zn–Ni–Mg–Cu Casting Aluminum Alloy

Strength of Materials ◽

10.1007/s11223-019-00098-1 ◽

2019 ◽

Vol 51 (4) ◽

pp. 534-540

Author(s):

D. H. Chen ◽

Z. Chen ◽

X. R. Zhu ◽

X. D. Wang ◽

X. L. Hong

Keyword(s):

Tensile Strength ◽

Aluminum Alloy ◽

Eutectic Phase ◽

Casting Aluminum Alloy ◽

Casting Aluminum

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Morphology of High-Performance Rigid-Rod Polymer Fibers and Molecular Composites

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010015366x ◽

1989 ◽

Vol 47 ◽

pp. 338-339

Author(s):

W.W. Adams ◽

S. J. Krause

Keyword(s):

Tensile Strength ◽

High Performance ◽

Liquid Crystalline ◽

Molecular Level ◽

Synergistic Effects ◽

Tensile Modulus ◽

Commercial Development ◽

The Matrix ◽

Molecular Composites ◽

Rigid Rod

Rigid-rod polymers such as PBO, poly(paraphenylene benzobisoxazole), Figure 1a, are now in commercial development for use as high-performance fibers and for reinforcement at the molecular level in molecular composites. Spinning of liquid crystalline polyphosphoric acid solutions of PBO, followed by washing, drying, and tension heat treatment produces fibers which have the following properties: density of 1.59 g/cm3; tensile strength of 820 kpsi; tensile modulus of 52 Mpsi; compressive strength of 50 kpsi; they are electrically insulating; they do not absorb moisture; and they are insensitive to radiation, including ultraviolet. Since the chain modulus of PBO is estimated to be 730 GPa, the high stiffness also affords the opportunity to reinforce a flexible coil polymer at the molecular level, in analogy to a chopped fiber reinforced composite. The objectives of the molecular composite concept are to eliminate the thermal expansion coefficient mismatch between the fiber and the matrix, as occurs in conventional composites, to eliminate the interface between the fiber and the matrix, and, hopefully, to obtain synergistic effects from the exceptional stiffness of the rigid-rod molecule. These expectations have been confirmed in the case of blending rigid-rod PBZT, poly(paraphenylene benzobisthiazole), Figure 1b, with stiff-chain ABPBI, poly 2,5(6) benzimidazole, Fig. 1c A film with 30% PBZT/70% ABPBI had tensile strength 190 kpsi and tensile modulus of 13 Mpsi when solution spun from a 3% methane sulfonic acid solution into a film. The modulus, as predicted by rule of mixtures, for a film with this composition and with planar isotropic orientation, should be 16 Mpsi. The experimental value is 80% of the theoretical value indicating that the concept of a molecular composite is valid.

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PEMANFAATAN GLISERIN DARI RESIDU GLISERIN SEBAGAI PLASTICIZER UNTUK PEMBUATAN BIOPLASTIK DENGAN BAHAN BAKU PATI BONGGOL PISANG KEPOK

Jurnal Teknik Kimia USU ◽

10.32734/jtk.v5i4.1551 ◽

2017 ◽

Vol 5 (4) ◽

pp. 26-32 ◽

Cited By ~ 1

Author(s):

Azaria Robiana ◽

M. Yashin Nahar ◽

Hamidah Harahap

Keyword(s):

Tensile Strength ◽

Hydrogen Bonding ◽

Fatty Acid ◽

Maximum Yield ◽

Sem Analysis ◽

Water Molecules ◽

Banana Weevil ◽

Gelatinization Temperature ◽

Recharge Area ◽

Maximum Quantity

Glycerin residue is waste oleochemical industry that still contain glycerin. To produce quality and maximum quantity of glycerin, then research the effect of pH acidification using phosphoric acid. Glycerin analysis includes the analysis of pH, Fatty Acid and Ester (FAE), and analysis of the levels of glycerin. The maximum yield obtained at pH acidification 2 is grading 91,60% glycerin and Fatty Acid and Ester (FAE) 3,63 meq/100 g. Glycerin obtained is used as a plasticizer in the manufacture of bioplastics. Manufacture of bioplastics using the method of pouring a solution with varying concentrations of starch banana weevil (5% w/v and 7% w/v), variations of the addition of glycerin (1 ml, 3 ml, 5 ml and 7 ml), and a variety of gelatinization temperature (60°C, 70°C, and 80°C). Analysis of bioplastics include FTIR testing, tensile strength that is supported by SEM analysis. The results obtained in the analysis of FTIR does not form a new cluster on bioplastics starch banana weevil, but only a shift in the recharge area only, it is due to the addition of O-H groups originating from water molecules that enter the polysaccharide through a mechanism gelatinitation that generates interaction hydrogen bonding strengthened. The maximum tensile strength of bioplastics produced at a concentration of starch 7% w/v, 1 ml glycerine and gelatinization temperature of 80°C is 3,430 MPa. While the tensile strength bioplastic decreased with increasing glycerin which can be shown from the results of SEM where there is a crack, indentations and lumps of starch insoluble.

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