Study of Residual Stresses Distribution Generated from Milling of Magnesium Alloy Parts

2014 ◽  
Vol 657 ◽  
pp. 18-22 ◽  
Author(s):  
Bogdan Chirita ◽  
Nicolae Catalin Tampu
Keyword(s):  
Mechanical Properties ◽  
Magnesium Alloy ◽  
Residual Stresses ◽  
Surface Quality ◽  
Specific Weight ◽  
Superficial Layer ◽  
Medical Industry ◽  
Alloy Part

Magnesium alloys exhibit a very good ratio of mechanical properties versus specific weight, thus making it an important choice for parts used in automotive, aeronautic and medical industry. The distribution of residual stress in the superficial layer of the material is regarded as one of the factors defining the surface quality of a machined part. It is therefore important to know this distribution as it is closely related to fatigue and corrosion resistance, especially for the parts working in aggressive environments (i.e. biomedical devices). The present paper focuses on the determination of the residual stresses induced in a magnesium alloy part processed by milling, and their effects on surface quality.

scholarly journals Effect of High Speed Milling Process Parameters on the Milling Force and Surface Topography of AM50A Magnesium Alloy

2018 ◽  
Vol 36 (1) ◽  
pp. 124-131
Author(s):  
Hongji Zhang ◽  
Yuanyuan Ge ◽  
Hong Tang ◽  
Yaoyao Shi ◽  
Zengsheng Li
Keyword(s):  
Magnesium Alloy ◽  
Surface Quality ◽  
High Speed ◽  
Milling Process ◽  
Spindle Speed ◽  
Feed Speed ◽  
Milling Force ◽  
High Speed Milling ◽  
Milling Parameters

Within the scope of high speed milling process parameters, analyzed and discussed the effects of spindle speed, feed rate, milling depth and milling width on milling forces in the process of high speed milling of AM50A magnesium alloy. At the same time, the influence of milling parameters on the surface roughness of AM50A magnesium alloy has been revealed by means of the measurement of surface roughness and surface micro topography. High speed milling experiments of AM50A magnesium alloy were carried out by factorial design. Form the analysis of experimental results, The milling parameters, which have significant influence on milling force in high speed milling of AM50A magnesium alloy, are milling depth, milling width and feed speed, and the nonlinear characteristics of milling force and milling parameters. The milling force decreases with the increase of spindle in the given mill parameters. For the effects of milling parameters on surface quality of the performance, in the milling depth and feeding speed under certain conditions with the spindle speed increases the surface quality of AM50A magnesium alloy becomes better with the feed speed increases the surface quality becomes poor. When the spindle speed is greater than 12000r/min, the milling depth is less than 0.2mm, and the feed speed is less than 400mm/min, the milling surface quality can be obtained easily.

Effect of Atmosphere and Holding Time on the Quality of Surface and Mechanical Properties of the Cold-Rolling Plate of Fe-42% Ni (4J42)

2012 ◽  
Vol 560-561 ◽  
pp. 655-660
Author(s):  
Li Juan Li ◽  
Li Hua Liu ◽  
Jing Wang
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Yield Strength ◽  
Cold Rolling ◽  
Surface Quality ◽  
Annealing Process ◽  
Holding Time ◽  
Annealing Condition ◽  
Nitrogen Ratio

In order to guide atmosphere annealing process in industry, the effect of atmosphere and holding times on the surface quality and mechanical properties of the cold-rolling plate of Fe-42% Ni (4J42) was studied. It is found that in the laboratory, surface qualities of all the samples annealed at different annealing condition are all good enough. When the ratio of hydrogen and nitrogen is below 70%:30%, at different holding time, with increasing of H2 proportion, 4J42’s tensile strength and yield strength all increases, and the hardness declines. And except H2:N2=70%:30, when holding time is less than or equal to 1.2min, at different ratio of hydrogen and nitrogen, holding time will influence 4J42’s mechanical properties little. So combine requires in industry with the experiment results, it can be concluded that for 4J42 alloy, annealing at atmosphere of hydrogen nitrogen ratio is less than 70%:30% for about 1.2min is appropriate to atmosphere annealing process in industry.

Characterization and Evaluation of Mechanical Properties and Residual Stress in Aluminum-Magnesium Alloys Welded by the FSW Process

2020 ◽  
Vol 1012 ◽  
pp. 349-353
Author(s):  
D.B. Colaço ◽  
M.A. Ribeiro ◽  
T.M. Maciel ◽  
R.H.F. de Melo
Keyword(s):  
Mechanical Properties ◽  
Residual Stress ◽  
Residual Stresses ◽  
Welding Process ◽  
Bending Test ◽  
Uniaxial Tensile ◽  
Uniaxial Tensile Test ◽  
Friction Stir ◽  
Aluminum Magnesium Alloys

The demand for lighter materials with suitable mechanical properties and a high resistance to corrosion has been increasing in the industries. Therefore, aluminum appears as an alternative due to its set of properties. The aim of this work was to evaluate residual stress levels and mechanical properties of welded joints of Aluminum-Magnesium alloy AA 5083-O using the Friction Stir Welding process. For mechanical characterization were performed a uniaxial tensile test, Vickers hardness, bending test and, finally, the determination of residual stresses. It was concluded that welding by FSW process with an angle of inclination of the tool at 3o, established better results due to better mixing of materials. The best results of tensile strength and a lower level of residual stresses were obtained using a tool rotation speed of 340 RPM with welding advance speed of 180 mm/min and 70 mm/min.

scholarly journals Use of fractal analysis to evaluate the surface quality of agricultural machinery parts

2020 ◽  
Vol 17 ◽  
pp. 00189
Author(s):  
Oleg Bavykin ◽  
Tatyana Levina ◽  
Vladlena Matrosova ◽  
Anatoly Klochkov ◽  
Vitaliy Enin
Keyword(s):  
Time Series ◽  
Computer Program ◽  
Surface Quality ◽  
Fractal Analysis ◽  
Hurst Exponent ◽  
High Accuracy ◽  
Agricultural Machinery ◽  
Fractal Characteristics

The research of the determination of the fractal characteristics of the surface of a material proposes the use of a stationary profilograph and a computer program for calculating the Hurst exponent. The low accuracy of fractal analysis using the well-known computer program Fractan is revealed. A computer program developed in VBA for the fractal analysis of the time series is described. The high accuracy of the algorithms for calculating the Hurst exponent incorporated in this program is shown.

Investigation of Sectoral Scanning in Selective Laser Melting

2010 ◽  
Author(s):  
Evren Yasa ◽  
Jan Deckers ◽  
Jean-Pierre Kruth ◽  
Marleen Rombouts ◽  
Jan Luyten
Keyword(s):  
Mechanical Properties ◽  
Residual Stresses ◽  
Laser Beam ◽  
Surface Quality ◽  
Selective Laser Melting ◽  
Random Order ◽  
Laser Source ◽  
Metal Powders ◽  
Laser Melting ◽  
Powder Bed

Selective laser melting (SLM), a powder metallurgical (PM) additive manufacturing (AM) technology, is able to produce fully functional parts directly from standard metal powders without using any intermediate binders or any additional post-processing steps. During the process, a laser beam selectively scans a powder bed according to the CAD data of the part to be produced and completely melts the powder particles together. Stacking and bonding two-dimensional powder layers in this way, allows production of fully dense parts with any geometrical complexity. The scanning of the powder bed by the laser beam can be achieved in several different ways, one of which is island or sectoral scanning. In this way, the area to be scanned is divided in small square areas (‘sectors’) which are scanned in a random order. This study is carried out to explore the influence of sectoral scanning on density, surface quality, mechanical properties and residual stresses formed during SLM. The experiments are carried out on a machine with an Nd:YAG laser source using AISI 316L stainless steel powder. As a result of this experimental study, it is concluded that sectoral scanning has some advantages such as lower residual stresses and better surface quality. However, the selection of parameters related to sectoral scanning is a critical task since it may cause aligned porosity at the edges between sectors or scanned tracks, which is very undesired in terms of mechanical properties.

scholarly journals Determination of the Hot Cracking Tendency of a Twin-Roll Cast AZ31 Magnesium Alloy by Means of Gleeble Tests

2018 ◽  
Vol 918 ◽  
pp. 40-47
Author(s):  
Heike Wemme ◽  
Christina Krbetschek ◽  
Madlen Ullmann ◽  
Anna Freigang ◽  
Stefan Plach ◽  
...  
Keyword(s):  
Magnesium Alloy ◽  
Az31 Alloy ◽  
Hot Cracking ◽  
Az31 Magnesium Alloy ◽  
Cast Magnesium ◽  
Twin Roll Cast ◽  
Twin Roll ◽  
Cracking Tendency

The knowledge about the formation of hot cracking in magnesium alloys, such as in twin-roll cast magnesium sheets and strips, is fundamental for a good quality of the strips during the further processing by rolling or welding and minimize the reject. Hot cracking often occurs in the so-called mushy zone, when solid phases and melt coexist, at temperatures where the material no longer exhibits ductility. For the evaluation of the hot cracking tendency of an alloy, the width of the HTBR (High-temperature brittleness range) can be used. On the basis of a test on a Gleeble HDS-V40, the HTBR was determined for a twin-roll cast AZ31 magnesium alloy. The transition between ductile forming behaviour and complete brittle reaction of the AZ31 alloy is confirmed by the observation of the fracture surfaces (determination of the fracture type) in the scanning electron microscope (SEM) and is located at 555 °C. The HTBR shows a range 35 K.

The Influence of Burnishing Parameters on the Surface Quality of Bars Made from AZ61 Magnesium Alloy

2013 ◽  
Vol 837 ◽  
pp. 135-140
Author(s):  
Gheorghe Mustea ◽  
Gheorghe Brabie
Keyword(s):  
Magnesium Alloy ◽  
Surface Quality ◽  
Magnesium Alloys ◽  
Working Process ◽  
Turning Operation ◽  
Az61 Magnesium Alloy ◽  
Burnishing Process ◽  
Abrasive Tools ◽  
Machined Surfaces

In the machining of the magnesium and magnesium alloys, some difficulties are encountered during working process. Thus, in the case of turning operation, when phenomena like: splinter self-ignition and flank built-up occur during machining, special tools and coolants are required in order to diminish the effects of such phenomena. In the case of grinding operation of the magnesium and its alloys, other phenomena like: adhesion between the abrasive tools and processing materials can cause explosions and hence such operation must be conducted in special conditions. A solution that can be applied to avoid such phenomena and effects is represented by the utilization of the burnishing operation. In the present study, the influence of the burnishing process on the quality of the machined surfaces of parts made from AZ61 magnesium alloy was performed. The quality of the burnished surfaces was analyzed in terms of the roughness and hardness parameters, the parameters with the greatest influence on surfaces roughness and hardness being the burnishing feed, burnishing speed and burnishing pressure

Numerical simulation of air purging conditions during steel sheet temper rolling process

2017 ◽  
Vol 08 (01) ◽  
pp. 1750007 ◽  
Author(s):  
Siyu Dai ◽  
Yonglin Kang ◽  
Guoming Zhu ◽  
Xiaofei Zheng ◽  
Yuhui Wen
Keyword(s):  
Mechanical Properties ◽  
Numerical Simulation ◽  
Surface Quality ◽  
Working Conditions ◽  
Steel Sheet ◽  
Rolling Process ◽  
Simplified Model ◽  
Temper Rolling ◽  
Structured Grids

The application of the lubricant in the temper rolling process of tinplate manufacturing improves the mechanical properties and surface quality of the steel sheet. The removal of the residual lubricant deserves and has rarely been studied via numerical simulation. A simplified model of a single stand temper mill was established and was discretized into cells of block-structured grids. The criterion whether the lubricant could be removed was decided via multiphase simulation of a smaller model. Three parameters, the gap between the deflector and the rolls, the length of an additional baffle and the velocity of the purging air, were considered and scores of different working conditions were performed. The shapes of the steel sheet between the temper rolls and the bridle roll were also studied to screen out the conditions that the sheet could move steadily.

Influence of the Corrosion Surrounding on Surface Quality of Grounded Hardened Steels

2011 ◽  
Vol 496 ◽  
pp. 25-29 ◽  
Author(s):  
Martin Novák
Keyword(s):  
Surface Roughness ◽  
Residual Stresses ◽  
Surface Quality ◽  
Cutting Conditions ◽  
Dynamic Force ◽  
Quality Changes ◽  
Hardened Steels

This paper deals with study of surface quality changes of hardened steels that grounded with given cutting conditions. The samples of hardened steels are in corrosion chamber dynamic loaded by dynamic force and we observed changes of surface quality in parameters of surface roughness, residual stresses and material portion of profile. Aim of this experiment is evaluate of surface quality in depend on influence of corrosion surrounding and using different cutting conditions during grinding of hardened steels samples.

Vibromechanic Way to Remove Residual Stresses

2014 ◽  
Vol 1064 ◽  
pp. 103-107
Author(s):  
Andrey Albertovich Korolev ◽  
Albert Viktorovich Korolev ◽  
Aleksandr Aleksandrovich Fomin ◽  
Sergey Aleksandrovich Savran ◽  
Andrey Fyodorovich Balaev ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Thermal Treatment ◽  
Residual Stresses ◽  
Ultrasonic Treatment ◽  
Process Efficiency ◽  
Mechanical Stabilization

The article describes the process efficiency of ultrasonic mechanical stabilization of details in comparison with the conventional thermal treatment. It is shown that ultrasonic treatment enhances the productivity and quality of manufactured details. As a result of the proposed stabilizing treatment the relaxation of residual stresses, the required geometry, such as waviness and ovality, as well as necessary mechanical properties are ensured.

Sign in / Sign up

Export Citation Format

Share Document