The Effect of Tin and Heat Treatment in Brass on Microstructure and Mechanical Properties for Solving the Cracking of Nut and Bolt

2013 ◽  
Vol 389 ◽  
pp. 237-244
Author(s):  
Wichan Chuaiphan ◽  
Loeshpahn Srijaroenpramong ◽  
Dumrongrit Pinpradub

This work studied the effect of tin (1%Sn) addition in brass 60%Cu+40%Zn (commercial grade) by casting process conducted poured melt metals inside a sand mould and heat treatment in cast brass on microstructure and mechanical properties for solving the cracking of nut and bolt. Three conditions of brass sample for experiment viz.- brass 60%Cu + 40%Zn (commercial grade), brass 60%Cu + 39%Zn+1%Sn (as-cast) and brass 60%Cu+39% Zn+1%Sn (precipitation hardening). The microstructure of specimens all condition, it was found that consists of α phase and β phase. Which brass addition 1% Sn, the β phase content in α phase matrix structure more than brass commercial grade. For microstructure of brass produce by precipitation hardening, shape of α phase are slender and long which have slight distributed in β-phase. The mechanicals properties, that is hardness, ultimate tensile strength and compressive strength. It was found that the brass 60%Cu+39% Zn+1%Sn (precipitation hardening), all test mechanical properties it was higher than the all samples condition. This results can be explain incharacterization of microstructure to gives deformation of copper alloy.

2018 ◽  
Vol 913 ◽  
pp. 109-117 ◽  
Author(s):  
Qing Yun Zhao ◽  
Si Rui Cheng ◽  
Li Dong Wang ◽  
Li Min Dong ◽  
Feng Lei Liu

The effects of heat treatment on microstructure and mechanical properties of Ti-38644 alloy were investigated by scanning electron microscope (SEM) and transmission electron microscopy (TEM) as well as uniaxial tensile test. The results show that when the solution temperature is lower than 845°C, the microstructure of Ti-38644 alloy is equiaxed β phase with the grain size of 20μm, and the tensile strength is about 960MPa. As raising solution temperature to 860°C, the grain size of Ti-38644 alloy increases to 100μm and the tensile strength decreased to 870MPa. There are a large number of secondary α phase precipitated from the grain boundaries and within grain of β phase undergoing aging treatment. Secondary α phase coarsens with increasing the aging temperature, leading to the decrease of tensile strength. After solution treatment at 815°C for 1.5h, water quenching plus aging at 520°C for 10h, air cooling, Ti-38644 alloy shows a better mechanical property with the tensile strength 1330MPa, elongation and reduction of area 10% and 45% respectively.


2005 ◽  
Vol 488-489 ◽  
pp. 151-154
Author(s):  
Weichao Zheng ◽  
Xiao Li Sun ◽  
Peijie Li ◽  
Daben Zeng ◽  
L.B. Ber

Effect of heat treatment on the microstructure and mechanical properties of high purity MA2-1(Mg-5wt.%Al-1wt.%Zn-0.4wt.%Mn) alloy sheet were investigated. X-ray diffraction analysis indicated that the microstructure of high purity MA2-1 alloy sheet annealed consisted of α-Mg solid solution, β (Mg17Al12) phase and Al-Mn phases such as Al6Mn and Al10Mn3. β phase dissolved into α-Mg solid solution during the solution treatment and formed supersaturated α-Mg solid solution. After aging at the temperatures of 423 K, 473 K and 523 K for 12 hours, β phase precipitated from the supersaturated α-Mg solid solution. Optical microscope observation found that the grain size of the MA2-1 alloy sheet became larger after heat treatment. As a result, the mechanical properties of the MA2-1 alloy sheet such as the tensile strength and yield strength declined after the heat treatment.


2020 ◽  
Vol 321 ◽  
pp. 11046
Author(s):  
Xu Enen ◽  
Tian Yanwen ◽  
Hao Fang ◽  
Cu Linin ◽  
Du Yuxuan ◽  
...  

In this paper, the microstructure evolution and mechanical properties fluctuation of Ti-6Al-2Zr-1Mo-1V forging state bar after the first stage heat treatment at 950℃~955℃ and the second stage heat treatment at 760℃~840℃ were studied. In the first stage of heat treatment, the content of primary α and the tensile strength decreases with the increase of temperature, and the high temperature duration time is obviously prolonged. During the second stage of heat treatment, the metastable β phase precipitates third α phase, and with the increase of temperature, the tensile strength increases and the high temperature duration time prolongs.


Materials ◽  
2020 ◽  
Vol 13 (2) ◽  
pp. 478
Author(s):  
Zheyu He ◽  
Hao He ◽  
Jia Lou ◽  
Yimin Li ◽  
Dongyang Li ◽  
...  

Ti6Al4V alloy has been considered as a key component used in ultrasonic scalpels. In this series of papers, the fabrication, structure, and mechanical and ultrasonic properties of medical Ti6Al4V alloys suitable for ultrasonic scalpel are studied systemically. These alloys with low elastic modulus and present a typical bimodal microstructure with relatively high β phase content (~40%) and lamellar α thickness of ≤ 0.9 µm. In the first paper, the relationship between the microstructure and mechanical properties of hot-rolled Ti6Al4V alloys treated by heating treatment is discussed. In the second paper, the dependence of the ultrasonic properties on the microstructure of the heat-treated Ti6Al4V alloys is reported. With increasing solid solution temperature, the content and size of the primary α phase decrease. In contrast, the content and size of the lamellar α phase increase. Additionally, the β phase content first increases and then decreases. The microstructure of Ti6Al4V alloys could be slightly changed by aging treatment. When the solid solution treatment temperature increases to 980 °C from 960 °C, the average size of the lamellar α phase in the alloys increases by 1.1 µm. This results in a decrease in the average yield strength (93 MPa). The elastic modulus of alloys is mainly controlled by the β phase content. The microstructure of alloys by solution-treatment at 960 °C shows the highest β phase content and lowest average elastic modulus of 99.69 GPa, resulting in the minimum resonant frequency (55.06 kHz) and the highest average amplitude (21.48 µm) of the alloys at the length of 41.25 mm.


2016 ◽  
Vol 682 ◽  
pp. 77-82
Author(s):  
Janusz Krawczyk ◽  
Łukasz Frocisz ◽  
Robert Dąbrowski ◽  
Edyta Rożniata ◽  
Tomasz Śleboda

Two near β titanium alloys (Ti-3Al-8V-6Cr-4Mo-4Zr and Ti-10V-2Fe-3Al) were investigated in his research. Both materials contained disperse precipitations of α phase in β phase matrix. In the case of Ti-3Al-8V-6Cr-4Mo-4Zr alloy clear segregation of alloy constituents, resulting from casting process, were observed. This segregation caused different susceptibility to α phase precipitation in dendritic and interdendritic areas in the microstructure of the investigated alloy. The influence of the temperature, strain and processing time on α phase dissolution was determined. Gleeble compression tests were performed on both of the investigated alloys. The research showed different character of the influence of strain rate and processing time on the temperature of α phase dissolution for each alloy. The effect of heat treatment on α phase dissolution during ageing of the investigated alloys was also determined. The possibility of obtaining homogenous microstructure in these alloys by properly designed heat treatment was also discussed.


10.30544/423 ◽  
2019 ◽  
Vol 25 (2) ◽  
pp. 147-162
Author(s):  
Franklin Amaechi Anene ◽  
Nkem Emelike Nwankwo ◽  
Victor Ugochukwu Nwoke

The effect of dopant and heat treatment on the microstructure and mechanical properties of Nickel-aluminum bronze (Cu-10%Al-5%Ni-5%Fe-x%Mo) were extensively investigated. The cast samples were heat treated through different processes, including solutionizing, quenching, and aging; their microstructures were examined using an optical microscope, scanning electron microscopy and energy dispersive spectroscopy analysis and their mechanical properties determined. The microstructure of the as-cast samples consisted of Cu-rich ‘α-phase, ‘κ-phases and small volume fraction of β'-phase while solutionizing transformed the β'-phase to a homogenous β-phase, α, and κ phases. Quenching transformed all β phase to β'-phase, however, aging the alloy precipitated fine dispersive strengthening κ-phases from the quenched microstructure. The results of the mechanical tests showed that the aged samples had improved excellent mechanical properties compared to the as-cast samples. Compared to the base alloy, the tensile strength and hardness of the aged 2% Mo sample increased by 58% and 55%, respectively while the impact strength and elongation decreased by 27% and 22%, respectively. Similarly, the tensile strength and hardness of the aged 3% Mo sample increased by 44% and 49%, respectively, while the impact strength and % elongation decreased by 23.9% and 24.9%, respectively.


2018 ◽  
Vol 910 ◽  
pp. 155-160 ◽  
Author(s):  
An Jin Liu ◽  
Lin Wang ◽  
Hua Xiang Dai

Microstructure evolution and compression property of Ti-10V-2Fe-3Al titanium alloy were studied in this paper. Solution treatments were performed at temperature ranging from 710°C to 830°C and some followed by aging treatment. Ti-10V-2Fe-3Al alloys with α+β phase show higher mechanical properties compared with single β phase alloy. With the increase of solution temperature, the content of equiaxed α phase decrease. Consequently, the strength of the alloy increases while the plasticity drops down. The highest yield strength value of 1668 MPa was obtained in the sample treated by 770°C solution treated for 2 hours then water quenched and followed by 520°C aging for 8 hours then air cooled. The stress induced martensite α'' phase appeared after SHPB dynamic compression in the sample solution treated at 830°C.


2019 ◽  
Vol 2019 ◽  
pp. 1-9 ◽  
Author(s):  
S. Souissi ◽  
N. Souissi ◽  
H. Barhoumi ◽  
M. ben Amar ◽  
C. Bradai ◽  
...  

In this study, the effects of squeeze casting process and T6 heat treatment on the microstructure and mechanical properties of 2017A aluminum alloy were investigated with scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDS), differential scanning calorimetry (DSC), and microhardness and tensile tests. The results showed that this alloy contained α matrix, θ-Al2Cu, and other phases. Furthermore, the applied pressure and heat treatment refines the microstructure and improve the ultimate tensile strength (UTS) to 296 MPa and the microhardness to 106 HV with the pressure 90 MPa after ageing at 180°C for 6 h. With ageing temperature increasing to 320°C for 6 h, the strength of the alloy declines slightly to 27 MPa. Then, the yield strength drops quickly when temperature reaches over 320°C. The high strength of the alloy in peak-aged condition is caused by a considerable amount of θ′ precipitates. The growth of θ′ precipitates and the generation of θ phase lead to a rapid drop of the strength when temperature is over 180°C.


Metals ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 857 ◽  
Author(s):  
Gyu Jeon ◽  
Ki Kim ◽  
Jung-Hwa Moon ◽  
Chul Lee ◽  
Whi-Jun Kim ◽  
...  

This study demonstrates the feasibility of a novel casting process called tailored additive casting (TAC). The TAC process involves injecting the melt several times to fabricate a single component, with a few seconds of holding between successive injections. Using TAC, we can successfully produce commercial-grade automotive steering knuckles with a tensile strength of 383 ± 3 MPa and an elongation percentage of 10.7 ± 1.1%, from Al 6061 alloys. To produce steering knuckles with sufficient mechanical strength, the composition of an Al 6061 alloy is optimized with the addition of Zr, Zn, and Cu as minor elements. These minor elements influence the thermal properties of the melt and alloy, such as their thermal stress, strain rate, shrinkage volume, and porosity. Optimal conditions for heat treatment before and after forging further improve the mechanical strength of the steering knuckles produced by TAC followed by forging.


2015 ◽  
Vol 816 ◽  
pp. 804-809 ◽  
Author(s):  
Xiao Yun Song ◽  
Yong Ling Wang ◽  
Wen Jing Zhang ◽  
Song Xiao Hui ◽  
Wen Jun Ye

The effects of different duplex annealing treatments on the microstructure and mechanical properties of Ti62421S alloy plate were studied by optical microscope (OM), scanning electron microscope (SEM), electron probe microanalysis (EPMA) and tensile tests, The experimental results indicated that the original microstructure of Ti62421S was composed of primary α phase (αp) and intergranular β phase. With the increase of first-stage annealing temperature, the volume fraction of equiaxed αp phase decreased. In contrast, the content of transformed β structure (βt) increased, and the width of lamellar secondary α phase (αs) in βt increased. Consequently, the yield strength (σ0.2) and ultimate tensile strength (σb) at room temperature and 600°C increased, while the elongation (δ5) declined. After 1000°C/2h/AC+ 600°C/2h/AC duplex annealing treatment, Ti62421S alloy plate showed superior tensile properties. The values of σb and δ5 at room temperature reached 1133MPa and 6%, as well as the value of σb at 600°C exceeded 710MPa.


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