Study on the surface quality of 60vol% SiCp/Al2024 composites with large-grained

In this paper, the finite element cutting simulation model with irregular distribution of multiple particles is established, the stress and strain distribution of SiC particles in the process of machining, as well as the material removal mechanism are analyzed. The effects of cutting velocity and feed per tooth on the surface quality of the material are also analyzed. The effect of feed per tooth on subsurface damage is revealed. The results show that in the micro-milling of SiCp/Al2024 composites, the particle removal form is mainly crushing and extraction. The surface defects of the workpiece mainly include pits, scratches, cracks, and extrusion damage. When the cutting velocity increases, the surface defects gradually change to crack, which can improve the surface quality of the workpiece. Increasing the feed per tooth will increase the surface defects of the workpiece and lead to poor surface quality. When the feed per tooth increased from 0.428 µm to 0.714 µm, the subsurface damage thickness increased from 35.2 µm to 47.3 µm.

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A study of conditions of surface defects formation when bar rolling at a bar and wire mill and methods of their elimination

Ferrous Metallurgy Bulletin of Scientific Technical and Economic Information ◽

10.32339/0135-5910-2021-10-1053-1059 ◽

2021 ◽

Vol 77 (10) ◽

pp. 1053-1059

Author(s):

I. A. Pankovets ◽

V. I. Voznaya ◽

A. V. Vedeneev ◽

M. N. Vereshchagin

Keyword(s):

Temperature Gradient ◽

Surface Quality ◽

Surface Defects ◽

Temperature Deformation ◽

Controlled Cooling ◽

Wire Mill ◽

The Core ◽

Local Overheating ◽

Rolling Production

Quality of long products surface is an important consumer property of it. In the process of measures elaboration aimed at the increase of long products surface quality, in particular of bars produced at the mill 370/150 of ОJSC “BMZ – managing company of holding “BMK”, studies were accomplished by metallographic laboratory. It was established that defects being revealed at the bars finishing, don’t relate to the quality of continuously casted billet (CCB), but formed in the process of deformation. Studies of the mechanism of surface defects formation on hot-rolled bar of rolling origin – deformation fissure and wrinkles were carried out. Results of numerical simulation of rolling in roughing group of stands at various temperature-deformation parameters presented. Regularities of formation of surface defects on the bar in the finished product were revealed. It was shown that the reason of the surface defects of rolling origin – deformation fissure and wrinkles was a high temperature gradient between the core and the surface of billet, originated from local overheating of surface in the angles zone of CCB resulted in nonuniformity of drawing out of different layers of the billet being deformed. To eliminate the defects, minimum possible temperature gradient between the surface and the core of a billet by controlled rolls cooling should be provided. By calculation, the maximum permissible temperature of the working surface of the rolls of the rough group of stands was established, and empirically the actual temperatures of the rolls with the current production technology, as well as the temperature of the rolls support bearings seats of the rolls were measured. The technical and technological possibilities for improving of rolling technology on a bar and wire mill in order to improve the surface quality of rolled bars were demonstrated. The existing technology was adjusted and new technological modes of rolling with controlled cooling of the rolls were established, which made it possible to significantly reduce the rejection of the finished product due to defects in rolling production. A device was proposed for the roughing group of stands, which enables to minimize the ingress of coolant onto the bar rolled.

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The Investigation of a Micro-Component Machined on a Custom-built Miniature Machine Tool

Jurnal Teknologi ◽

10.11113/jt.v59.2563 ◽

2012 ◽

Vol 59 (2) ◽

Author(s):

Syaimak Abdul Shukor

Keyword(s):

Surface Quality ◽

Milling Process ◽

Micro Milling ◽

Batch Size ◽

Geometrical Accuracy ◽

Custom Made ◽

Micro Parts ◽

Solid Carbide ◽

Steel Aisi

Custom-built Miniature Machine Tools (MMTs) are now becoming more popular with the demand for reduced energy consumption and workshop floor when machining small/medium batch size micro-components. This paper investigates the capability of a custom-built 4-axis MMT through machining an “adapted standard‟ of micro-testpiece. The experiments have been carried out in two different materials: Carbon Steel (AISI 1040) and Titanium Alloyed (TiAl6V4) using solid carbide flat end mill cutters with 0.6mm diameter. From here, the surface quality and geometrical accuracy of the machined testpiece are evaluated and analysed. The investigation has shown that acceptable geometrical accuracies and surface quality of the machined micro-parts can be achieved using the in-house developed MMT. These results show that the use of the custom-made MMT does not hinder the micro-milling process to produce a good and satisfactory surface quality (Ra=0.04-0.07μm) and acceptable geometrical accuracy.

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Machining a Micro-Scale Structure Using an in-House Developed Miniature Machine Tool

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.418-420.1502 ◽

2011 ◽

Vol 418-420 ◽

pp. 1502-1506

Author(s):

Abdul Shukor Syaimak

Keyword(s):

Surface Quality ◽

Machine Tools ◽

Milling Process ◽

Micro Milling ◽

Batch Size ◽

End Mill ◽

Geometrical Accuracy ◽

Custom Made ◽

Solid Carbide

Custom-built Miniature Machine Tools (MMTs) are now becoming more popular with the demand for reduced energy consumption and workshop floor when machining small/medium batch size micro-components. This paper investigates the capability of a custom-built 4-axis MMT through machining a micro-component demonstrator. The experiments have been carried out in Titanium Alloyed (TiAL6V4) using 0.6mm solid carbide flat end mill cutters. From here, the surface quality and geometrical accuracy of the machined testpiece are evaluated and analysed. The investigation has shown that acceptable geometrical accuracies and surface quality of the machined micro-demonstrator can be achieved using the in-house developed MMT. These results show that the use of the custom-made MMT does not hinder the micro-milling process to produce a good and satisfactory surface quality and acceptable geometrical accuracy.

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Experiment research on surface quality of high speed micro-milling stainless steel

2015 IEEE International Conference on Mechatronics and Automation (ICMA) ◽

10.1109/icma.2015.7237876 ◽

2015 ◽

Cited By ~ 1

Author(s):

Xinxin Zhang ◽

Jinkai Xu ◽

Zhanjiang Yu ◽

Zhichao Wang ◽

Huadong Yu

Keyword(s):

Stainless Steel ◽

Surface Quality ◽

High Speed ◽

Micro Milling ◽

Experiment Research

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Research on Subsurface Damage of Lapping Sapphire with Diamond Fixed Abrasive

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.866.143 ◽

2020 ◽

Vol 866 ◽

pp. 143-151

Author(s):

Jian Bin Wang ◽

Yong Qiang Tong ◽

Ben Chi Jiang ◽

Da Shu ◽

Gang Wang

Keyword(s):

Surface Quality ◽

Surface Damage ◽

Subsurface Damage ◽

Indentation Fracture ◽

Damage Layer ◽

Damage Depth ◽

The Difference ◽

Fixed Abrasive ◽

Free Abrasive

The depth of surface/subsurface damage layer is the key index of surface quality of sapphire. In this paper, that depth model of the surface/subsurface damage lay characterized by the crack length was established according to the mechanical theory of indentation fracture. The cutting relation between abrasive and workpiece and the difference of the depth of subsurface damage crack are analyzed. It is preliminarily estimated that the length of sub-surface damage crack of free abrasive sapphire is about 2.46 times that of fixed abrasive when considering only the contact hardness of abrasive grain under static load. Diamond abrasives with size of W20 were adopted to carry out experiments in free and fixed lapping methods. The results show that the surface/subsurface damage depth is 9.87μm and 3.63μm respectively. It is easier to obtain good sub-surface quality by using the fixed abrasive method than free abrasive at the same particle size.

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Study on Removal Mechanism and Surface Quality of High Volume Fraction SiCp/Al Composites Based on Meso-scale

10.21203/rs.3.rs-322809/v1 ◽

2021 ◽

Author(s):

Po Jin ◽

Qi Gao ◽

Quanzhao Wang ◽

Wenbo Li

Keyword(s):

Particle Size ◽

Surface Quality ◽

Feed Rate ◽

Volume Fraction ◽

High Volume ◽

Milling Process ◽

Subsurface Damage ◽

High Volume Fraction ◽

Removal Mechanism

Abstract The milling process of SiCp/Al composites with high volume fraction and large particle size has been studied in this paper. The stress and strain distribution of SiC reinforced particles and the removal mechanism of the material are analysed. The effects of milling depth and feed per tooth on surface quality were analysed. The effect of feed per tooth on the thickness of subsurface damage layer is revealed. The results show that in the end milling process of high volume fraction SiCp/Al composites, the blade diameter is larger relative to the particle size, which leads to the main removal forms of particle size: extrusion crushing and rolling crushing. The surface defects of the machined workpiece mainly include cavity, crack and delamination caused by extrusion of aluminum matrix. The surface quality of the machined workpiece can be improved by increasing the milling depth appropriately. The increase of the feed rate of each tooth will lead to the increase of the surface defect of the machined workpiece and the deterioration of the surface quality. When the feed rate per tooth increases from 4 to 8 μm, the thickness of subsurface damage increases from 47.7 to 60.5 μm. It is found that the ratio between the minimum cutting thickness of SiCp/Al composites and the radius of the cutting edge should be less than or equal to 4%.

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Experimental Study on Surface Quality in Micro-Milling of Single Crystal Superalloy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1136.196 ◽

2016 ◽

Vol 1136 ◽

pp. 196-202

Author(s):

Qi Gao ◽

Ya Dong Gong ◽

Yun Guang Zhou

Keyword(s):

Single Crystal ◽

Surface Quality ◽

Orthogonal Experiment ◽

Single Crystal Superalloy ◽

Micro Milling ◽

Range Analysis ◽

Milling Tool ◽

The Impact ◽

The Ideal

Single crystal Ni3Al-based superalloy has excellent comprehensive performance.To study the micro-milling surface quality of Ni3Al-based superalloy, this article used two-edged carbide alloy micro-milling tool with 0.8mm diameter, then orthogonal experiment of three factors and five levels was implemented to the micro-milling of typical single crystal Ni3Al-based superalloy IC10. The primary and secondary factors of the impact on the micro-milling surface quality were found from spindle speed, feed rate, milling depth by range analysis, and the ideal cutting process parameters combination was optimized and obtained, then its cutting mechanism and the reason of affecting the surface quality were analyzed. The experiment result has certain guiding significance to the micro-milling mechanism of single crystal superalloy.

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Damage Analysis for Multilayer Composite Material

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.912-914.3 ◽

2014 ◽

Vol 912-914 ◽

pp. 3-6

Author(s):

Yi Yong Yao ◽

Li Ping Zhao ◽

Sheng Hu ◽

Wen Jie Bai

Keyword(s):

Carbon Fiber ◽

Fiber Composite ◽

Stress And Strain ◽

Damage Analysis ◽

Technical Approach ◽

Carbon Fiber Composite ◽

Fiber Damage ◽

Damage Process ◽

Stress And Strain Distribution

After studying the influencing factors and interaction rules of the damage for reinforced carbon fiber in different jet medium on the basis of analyzing carbon fiber damage for traditional acupuncture process, a lower damage process scheme of preform based on jet for layered carbon fiber composite is proposed in this paper. Firstly, the carbon fiber puncture damage is clustered and formal described by using graph theory, which the analytical method for a complex combination of puncture damage is obtained successfully. Then the stress and strain distribution of carbon fiber puncture damage is analyzed through simulation. So this paper has proposed a new technical approach for improving the quality of the needle perform.

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