scholarly journals Novel Permanent Magnetic Surface Work Hardening Process for 60/40 Brass

Materials ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 6312
Author(s):  
Ayman M. Alaskari ◽  
Abdulaziz I. Albannai ◽  
Abdulkareem S. Aloraier ◽  
Meshal Y. Alawadhi ◽  
Tatiana Liptáková
Keyword(s):  
Feed Rate ◽  
Work Hardening ◽  
High Speed ◽  
Surface Hardness ◽  
Magnetic Surface ◽  
Material Surface ◽  
Ground Sample ◽  
The North ◽  
Surface Work ◽  
Steel Balls

Surface work hardening is a process of deforming a material surface using a thin layer. It hardens and strengthens the surface while keeping the core relatively soft and ductile to absorb stresses. This study introduces a permanent magnate surface work hardening under two opposite permanent poles of a magnet to investigate its influence on a brass surface. The gap between the brass and the north magnet pole—fixed in the spindle of a vertical machine—was filled with martensitic stainless steel balls. The rotational speed and feed rates were 500–1250 rpm and 6–14 mm min−1, respectively. The novel method improved the surface hardness for all parameters by up to 112%, in favor of high speed, and also increased yield by approximately 10% compared to ground samples. Surface roughness showed higher values for all speed–feed rate combinations compared to the ground sample. Nevertheless, it showed better roughness than other treated conditions with high and low feed rates. The ultimate tensile strength and ductility remained unchanged for all conditions other than the untreated brass. A factorial design and nonlinear regression analysis were performed to predict the microhardness equation and effectiveness of the independent variable—speed and feed rate—for the proposed process.

Experimental Investigations of Surface Hardening for Aviation Aluminum Alloy in High Speed Milling

2012 ◽  
Vol 426 ◽  
pp. 60-63 ◽  
Author(s):  
X.L. Fu ◽  
Y. Z. Pan ◽  
Xiao Qin Wang
Keyword(s):  
Aluminum Alloy ◽  
Work Hardening ◽  
Surface Hardening ◽  
High Speed ◽  
Cutting Speed ◽  
Surface Hardness ◽  
Experimental Investigations ◽  
Micro Hardness ◽  
Layer Depth ◽  
High Speed Milling

Surface hardening plays an important role in the evaluation of surface quality and performance of wear-resisting of components. Surface hardening of aluminum alloy 7050 is researched in high speed milling by means of micro-hardness experiments and formula. It is greatly influenced by different cutting speed and material. The relationship between surface hardness and cutting parameters are obtained and studied. The surface hardening is particularly sensitive to cutting speed and slightly to the width of cut. The effect of depth variant of machined layer on micro-hardness is analyzed, and the equation between work hardening capacity and layer depth is established to predict the harden layer depth in different conditions. The experiment results show that the work hardening capacity and layer depth in high speed cutting is greater than that in conventional cutting.

Investigation on Surface Integrity of STAVAX ESR AISI 420 Martensitic Stainless Steel by Cryogenically Treated Steel Balls with Low Plastic Burnishing Tool

2012 ◽  
Vol 504-506 ◽  
pp. 1347-1352
Author(s):  
Sivapraksam Thamizhmanii ◽  
K. Rajendran ◽  
Mohideen Rasool ◽  
Sulaiman Hassan
Keyword(s):  
Surface Roughness ◽  
Stainless Steel ◽  
Surface Integrity ◽  
Feed Rate ◽  
Martensitic Stainless Steel ◽  
Surface Hardness ◽  
Operating Parameters ◽  
Micro Hardness ◽  
Aisi 420 ◽  
Steel Balls

Low plasticity burnishing (LPB) is a new method of surface improvement, which raises the burnishing to the next level of sophistication. LPB can provide deep compression for improved surface characteristics. The study focuses on the surface roughness, micro-hardness and surface integrity aspects on soft AISI 420 STAVAX ESR martensitic stainless steel AISI 420 material. This material is pronounced as difficult to cut materials like titanium, Inconel 718 etc. The investigation of surface integrity was done on this materials in terms of operating parameters like sliding speed, feed rate and depth of penetration (DOP) identifying the predominant factors among the selected parameters. The steel balls used were cryogenically treated at sub zero temperature of -176 degrees. Sub-surface micro-hardness study were also done to asses the depth of compression altered zone, surface roughness and surface hardness. The process can be applied to critical components effectively as the LPB process has cycle time advantages and also low investment cost. This can be also realized by introducing on high speed machines. This process was studied by using cryogenically treated different ball diameters at various operating parameters. This also improved on concentricity of work material. More the depth of compression produced low surface roughness at low sliding speed, feed rate with larger ball diameter. The DOP also helps to improve on surface and sub-surface hardness and close roundness. There are limitations on DOP beyond which the surface deteriorated.

Effect of deep rolling parameters on surface integrity of LZ50 axles

2019 ◽  
Vol 33 (25) ◽  
pp. 1950298 ◽  
Author(s):  
Hao Fu ◽  
Yan Liu ◽  
Qian Xu ◽  
Xiulin Yan ◽  
Guiying Yang ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Compressive Stress ◽  
Surface Integrity ◽  
High Speed ◽  
Influence Factor ◽  
Surface Hardness ◽  
Material Surface ◽  
Feed Speed ◽  
Deep Rolling ◽  
Rolling Surface

Deep rolling is a surface treatment method by which a hydraulically controlled ball produces a specific pressure on material surface, causing plastic deformation and introducing compressive residual stresses. In this paper, LZ50 steel which is often used as high speed train axle is treated by deep rolling. Surface morphology was observed, and roughness, microhardness and residual stress were measured. Effects of deep rolling parameters (pressure, feed speed, speed, number of runs) on the surface integrity of LZ50 axles were studied systematically. The results show that the surface roughness decreases obviously after deep rolling compared with the original surface. The feed speed has greater influence than other parameters on surface roughness. The minimum roughness (Ra) can decrease to 0.14 [Formula: see text]m. The surface layer of LZ50 deforms in different degrees. Meanwhile, the surface stress state of LZ50 changes from tensile stress to compressive stress after deep rolling. The maximum residual compressive stress is 862 MPa. The main influence factor is pressure. However, for LZ50 axle, the surface hardness does not change significantly after deep rolling.

Research on the Influences of High-Speed Milling Parameters on Surface Work-Hardening

2013 ◽  
Vol 662 ◽  
pp. 273-276
Author(s):  
Jian Xin Pan ◽  
Qiang Li
Keyword(s):  
Work Hardening ◽  
High Speed ◽  
End Milling ◽  
Cutting Parameters ◽  
Processing Efficiency ◽  
High Speed Milling ◽  
Milling Parameters ◽  
Orthogonal Experiments ◽  
Surface Work

The orthogonal experiments of end milling were designed. Workpiece surfaces hardening were studied in high-speed milling. The results indicate that the degree of surface work-hardening in high-speed milling 8407 mold-steel is lower than that in conventional speed milling;By choosing the appropriate cutting parameters, to improve the surface quality of the workpieces and the processing efficiency is beneficial;Through changing the high-speed milling parameters to control the work hardening, the effect is not so obvious.

Numerical Analysis of Influence of Roughness of Material Surface on High-Speed Liquid Droplet Impingement

2019 ◽  
Vol 141 (3) ◽  
Author(s):  
Hirotoshi Sasaki ◽  
Yuka Iga
Keyword(s):  
Numerical Analysis ◽  
High Speed ◽  
Erosion Rate ◽  
Liquid Droplet ◽  
Material Surface ◽  
Liquid Droplets ◽  
Fluid Machinery ◽  
Droplet Impingement ◽  
Surface Liquid ◽  
Droplet Impingement Erosion

This study explains why the deep erosion pits are formed in liquid droplet impingement erosion even though the droplets uniformly impinge on the entire material surface. Liquid droplet impingement erosion occurs in fluid machinery on which droplets impinge at high speed. In the process of erosion, the material surface becomes completely roughened by erosion pits. In addition, most material surface is not completely smooth and has some degree of initial roughness from manufacturing and processing and so on. In this study, to consider the influence of the roughness on the material surface under droplet impingement, a numerical analysis of droplets impinging on the material surface with a single wedge and a single bump was conducted with changing offsets between the droplet impingement centers and the roughness centers on each a wedge bottom and a bump top. As results, two mechanisms are predicted from the present numerical results: the erosion rate accelerates and transitions from the incubation stage to the acceleration stage once roughness occurs on the material surface; the other is that deep erosion pits are formed even in the case of liquid droplets impinging uniformly on the entire material surface.

Cutting Temperature and Cutting Forces Investigation Based on the Taguchi Design Method when High-Speed Milling of Titanium Matrix Composites with PCD Tool

2016 ◽  
Vol 836-837 ◽  
pp. 168-174 ◽  
Author(s):  
Ying Fei Ge ◽  
Hai Xiang Huan ◽  
Jiu Hua Xu
Keyword(s):  
Cutting Force ◽  
Feed Rate ◽  
Cutting Forces ◽  
High Speed ◽  
Volume Fraction ◽  
Cutting Temperature ◽  
Cutting Speed ◽  
Depth Of Cut ◽  
High Speed Milling ◽  
Radial Depth

High-speed milling tests were performed on vol. (5%-8%) TiCp/TC4 composite in the speed range of 50-250 m/min using PCD tools to nvestigate the cutting temperature and the cutting forces. The results showed that radial depth of cut and cutting speed were the two significant influences that affected the cutting forces based on the Taguchi prediction. Increasing radial depth of cut and feed rate will increase the cutting force while increasing cutting speed will decrease the cutting force. Cutting force increased less than 5% when the reinforcement volume fraction in the composites increased from 0% to 8%. Radial depth of cut was the only significant influence factor on the cutting temperature. Cutting temperature increased with the increasing radial depth of cut, feed rate or cutting speed. The cutting temperature for the titanium composites was 40-90 °C higher than that for the TC4 matrix. However, the cutting temperature decreased by 4% when the reinforcement's volume fraction increased from 5% to 8%.

Effect of Machining Parameters and Wear Mechanism in Milling Mold Steel AISI-P20 and AISI-1050

2014 ◽  
Vol 590 ◽  
pp. 294-298
Author(s):  
Pichai Janmanee ◽  
Somchai Wonthaisong ◽  
Dollathum Araganont
Keyword(s):  
Wear Mechanism ◽  
Feed Rate ◽  
High Speed ◽  
Removal Rate ◽  
Milling Process ◽  
Depth Of Cut ◽  
Machining Parameters ◽  
Aisi P20 ◽  
Steel Aisi ◽  
Quality Surface

In this study, effect of machining parameters and wear mechanism in milling process of mold steel AISI-P20 and AISI-1050, using 10 mm twin flute type end mill diameter. The experimental results found that characteristics of milling surfaces and wear of the mill end were directly influenced by changes of parameters for all test conditions. As a result, the quality of milling surfaces also changed. However, mould steels which had the good quality surface is AISI-1050, with roughnesses of 2.120 μm. Quality milling surfaces were milled by using the most suitable parameter feed rate of 45 mm/min, a spindle speed of 637 rpm and a cut depth level of 3 mm, for both grades. Moreover, material removal rate and duration of the milling process, the milling end mills affect wear of the edge in every bite when the feed rate is low, high speed and level depth of cut at least. It was found that limited wear less will affect the surface roughness (Ra) represents the good quality surface.

scholarly journals The hardening of metals by rotating magnetic fields

1931 ◽  
Vol 130 (814) ◽  
pp. 514-523 ◽  
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Work Hardening ◽  
Rotating Magnetic Fields ◽  
Hardening Process ◽  
Hard Steel ◽  
Steel Balls ◽  
Hardened Condition

In a previous paper by the author experiments were described in which the hardness of various metals was increased by rotating them in a magnetic field. It had been observed that metals in a work-hardened condition, and in particular hard steel which had been super-hardened by the “Cloudburst” process of bombardment with steel balls, exhibit a propensity to become still harder by a process of ageing, the spontaneous increase of hardness commencing with the termination of the work-hardening process, and contiuning during a period of several hours or days.

The Effect of Airflow Speed as Cooling Media in the Hardening Process to the Hardness, Corrosion Rate and Fatigue Life of Medium Carbon Steel

2021 ◽  
Vol 1045 ◽  
pp. 40-49
Author(s):  
Sunardi Sunardi ◽  
Rina Lusiani ◽  
Erny Listijorini ◽  
Ruddy Santoso ◽  
Iman Saefuloh
Keyword(s):  
Fatigue Life ◽  
Barium Carbonate ◽  
Surface Hardness ◽  
Medium Carbon Steel ◽  
Holding Time ◽  
Material Surface ◽  
Airflow Rate ◽  
Aisi 1045 Steel ◽  
Aisi 1045 ◽  
1045 Steel

Carburizing is a method for obtaining a sturdy material surface. This hard surface is used for machine elements that intersect with other materials, so failure due to wear can be avoided. However, this increase in hardness has always been followed by decreased ductility. This condition certainly lowers the fatigue life of the material. For that, it is necessary to compromise between surface hardness and ductility. This study used AISI 1045 steel, which has a surface roughness of 0.4 and 4.7 μm with carburation media used, is a mixture of 80% coconut shell charcoal and 20% Barium carbonate. The sample was given the pack carburization treatment at 850°C and holding time for 3 hours, and then cooled in the open air. The samples were reheated at 850°C, holding time for 17 minutes, and then cooled with airflow at speeds of 10.34, 15.51, and 20.06 m/s for 30 minutes. This research shows that the surface of steel with a roughness of 0.4 μm has excellent performance with the hardness and corrosion level respectively 228.6 HV and 2.3586 mpy at cooling airflow rate of 20.06 m/s while the fatigue life of material occurs at the speed of airflow cooling 10.43 m/s.

Investigation of Surface Roughness and Material Removal Rate for High Speed Micro End Milling on PMMA

2015 ◽  
Vol 1115 ◽  
pp. 12-15
Author(s):  
Nur Atiqah ◽  
Mohammad Yeakub Ali ◽  
Abdul Rahman Mohamed ◽  
Md. Sazzad Hossein Chowdhury
Keyword(s):  
Surface Roughness ◽  
Material Removal Rate ◽  
Feed Rate ◽  
Material Removal ◽  
High Speed ◽  
End Milling ◽  
Removal Rate ◽  
Spindle Speed ◽  
Depth Of Cut ◽  
Micro End Milling

Micro end milling is one of the most important micromachining process and widely used for producing miniaturized components with high accuracy and surface finish. This paper present the influence of three micro end milling process parameters; spindle speed, feed rate, and depth of cut on surface roughness (Ra) and material removal rate (MRR). The machining was performed using multi-process micro machine tools (DT-110 Mikrotools Inc., Singapore) with poly methyl methacrylate (PMMA) as the workpiece and tungsten carbide as its tool. To develop the mathematical model for the responses in high speed micro end milling machining, Taguchi design has been used to design the experiment by using the orthogonal array of three levels L18 (21×37). The developed models were used for multiple response optimizations by desirability function approach to obtain minimum Ra and maximum MRR. The optimized values of Ra and MRR were 128.24 nm, and 0.0463 mg/min, respectively obtained at spindle speed of 30000 rpm, feed rate of 2.65 mm/min, and depth of cut of 40 μm. The analysis of variance revealed that spindle speeds are the most influential parameters on Ra. The optimization of MRR is mostly influence by feed rate. Keywords:Micromilling,surfaceroughness,MRR,PMMA

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