Some Observations in Grinding Surface Quality of FRCMC

2013 ◽  
Vol 770 ◽  
pp. 198-201 ◽  
Author(s):  
Xiao Yan Cao ◽  
Bin Lin ◽  
Yan Wang ◽  
Shao Lei Wang
Keyword(s):  
Surface Quality ◽  
Fiber Orientation ◽  
Surface Defects ◽  
Optical Measurement ◽  
Orientation Angle ◽  
Decisive Role ◽  
Ceramic Matrix Composites ◽  
Obtuse Angle ◽  
High Tech

FRCMCs have potential applications in aerospace and other high-tech fields. According to FRCMCs anisotropic and non-homogeneous structure, the composites surface characteristics are different from metal material. Fiber orientations play the decisive role in grinding surface quality of woven ceramic matrix composites. This paper investigates the relationship between fiber orientations and grinding surface quality. Using a non-contact optical measurement instrument, the method was developed on 2.5D SiO2/SiO2 composite. Through a series of measuring experiments, it was found that greater grinding surface quality occurred at a fiber orientation 90, but poorer grinding surface took place at a fiber orientation 0. Meanwhile there were less surface defects at acute fiber orientation angle than at obtuse angle. The research obtained will be an important technical support on improving the processing quality of FRCMC.

A Study on 3D Micro-Topographical Measurement of FRCMC Grinding Surface

2013 ◽  
Author(s):  
Xiaoyan Cao ◽  
Bin Lin ◽  
Yan Wang ◽  
Shaolei Wang
Keyword(s):  
Surface Topography ◽  
Surface Quality ◽  
Optical Measurement ◽  
Measurement Instrument ◽  
Ceramic Matrix Composites ◽  
Sampling Interval ◽  
High Tech ◽  
Starting Position ◽  
Sampling Conditions

Fiber-reinforced ceramic matrix composites (FRCMCs) have potential applications in aerospace and other high-tech fields. Meanwhile, it is significant to evaluate the grinding surface quality of FRCMCs. But according to FRCMCs’ anisotropic and non-homogeneous structure, it is difficult to evaluatethe surface quality with the traditionalmeasuring method used in metal material. The present paper studied the 3D micro-topographical measurement and evaluationfrom a new perspective. The research is based on some new discovery that the material enhanced fiber orientation played key role in micro-topographical of FRCMC grinding surface. Using a non-contact optical measurement instrument, the method was developed on 2.5D SiO2/SiO2 composite. Through a series of measuring experiments, we found that both starting position of measurement and sampling conditions affected on the measurement results. This paper recommendedoptimization measurement parameter valuesof sampling conditions, and also analyzedcharacteristics of the RCMC grinding surface topography on amplitude, wave distribution and surface supportcharacteristics in details. The results show that the optimal range of sampling interval is 40 μm to 70 μm, the range of sampling area is better more than 64mm2 and the range of sampling speed is 8 to 14mm/s. The measurement of surface topography is the bridge framed between the manufacture and parts performance, so theresearchobtained will be an important technical support on improvingthe processing quality of FRCMC.

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

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.

Research and Development of High-Quality Mechanical Engineering Products

2013 ◽  
Vol 329 ◽  
pp. 503-506
Author(s):  
Zhe Wen ◽  
Qian Dong
Keyword(s):  
Research And Development ◽  
Market Research ◽  
Decisive Role ◽  
Structure Design ◽  
High Tech ◽  
High Quality ◽  
Core Components ◽  
Software And Hardware ◽  
Quality Of Products

Computer is high-tech equipment in the age of information, and has been widely applied in all industries by relying on its sharing, universality, intelligence and other characteristics. Seen from the structural composition, software and hardware are two core components of computer, and play a decisive role in the quality of computer and its system in the actual work. Software development is a process for building up software system or software of system according to the needs of users; in high-quality software research and development, multiple aspects such as market research, demand analysis, structure design and model debugging are involved, and the quality of products can be ensured only if each operation link is strictly controlled.

Influence of Fiber Orientation on Machined Surface Quality in Milling of Unidirectional CFRP Laminates

2016 ◽  
Vol 1136 ◽  
pp. 137-142 ◽  
Author(s):  
Chang Ying Wang ◽  
Liang Wen ◽  
Cheng Dong Wang ◽  
Hong Zhou Zhang ◽  
Qing Long An ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Surface Morphology ◽  
Surface Quality ◽  
Fiber Orientation ◽  
Orientation Angle ◽  
Machined Surface ◽  
Cfrp Laminates ◽  
Pull Out ◽  
Machined Surface Quality ◽  
Fiber Orientation Angle

Machined surface quality is the deciding factor when evaluating the machinability of CFRP. This present work concerns the influence of fiber orientation on the machined surface quality of the machined surface in terms of surface morphology and surface roughness during milling of unidirectional T800/X850 CFRP laminates. Four group milling tests are conducted under the fiber orientation angle of 0°, 45°, 90° and 135°, respectively. For the fiber orientation angle of 0°, the machined defects are mainly fiber pull-out and fiber brittle fracture owing to interfacial debonding between the fibers and matrix resin. For the fiber orientation angle of 45°, the machined defects are mainly resin cavities and the surface morphology is rough and presents wavy fractures. For the fiber orientation angle of 90°, smooth or neat surface is observed except for the surface as the cutting tool cutting in the workpiece on which severe cracks are observed. For the fiber orientation angle of 135°, the surface is smooth with less fibers pull-out. Evaluation profile and surface roughness of the machined surfaces were measured as well. Dramatically fluctuate of the evaluation profile is observed for the fiber orientation angle of 45° with a high surface roughness Ra. Verification tests were also conducted on the multidirectional CFRP (cross-ply) laminates. It is indicated that the presence of the fiber orientation angle of 45° is the main factor leading to the decline of the machined surface quality.

Research Progress of Improving Surface Quality of Microcellular Foam Injection Parts

2011 ◽  
Vol 66-68 ◽  
pp. 2010-2016 ◽  
Author(s):  
Yue Wang ◽  
Guang Hong Hu
Keyword(s):  
Injection Molding ◽  
Surface Quality ◽  
Dimensional Stability ◽  
Surface Defects ◽  
Research Progress ◽  
Microcellular Foam ◽  
Counter Pressure ◽  
Foam Injection Molding ◽  
Application Scope

Microcellular foam injection parts have many advantages such as saving material and energy, reducing cycle time, and processing excellent dimensional stability. Despite these advantages, the low surface quality problems limit its application scope seriously. In this study, the microcellular foam injection molding principle and some surface defects were introduced, and the technologies to improve surface quality, such as Gas Counter Pressure (GCP), Rapid Heat Cycle Molding (RHCM), and Film Insulation were summarized in detail. Finally, the prospect of CAE technologies about microcellular foam injection molding was proposed.

Optical Simulation of Omnidirectional Inspection System for Screw Threads

2014 ◽  
Vol 625 ◽  
pp. 706-711
Author(s):  
Keun Park ◽  
Chang Hun Lee ◽  
Seung Woo Ra
Keyword(s):  
Surface Defects ◽  
Optical Measurement ◽  
Optical Simulation ◽  
Inspection System ◽  
Light Illumination ◽  
Screw Thread ◽  
Simulation Based ◽  
Screw Threads ◽  
Optical Paths

Machine vision systems have been used in the automatic inspection of screw threads using backlight illumination for the inspection of the screw thread profiles. In this study, an alternative inspection system based on front light illumination is developed to directly obtain thread images so that surface defects can be measured. To realize such an inspection system, an omnidirectional optical measurement device is proposed to obtain 360oimages of screws for inspection of whole thread regions. Optical simulation based on ray tracing is then performed to analyze optical paths and to optimize the image quality of the designed optical system.

Research on Tribological Properties of Environment-Friendly Nano-MoS2 Water-Based Rolling Liquid

2020 ◽  
Vol 861 ◽  
pp. 349-353
Author(s):  
Yan Li ◽  
Ren Dong Liu ◽  
Lei Xia ◽  
Rong Sheng Sun ◽  
Jian Jun Zhang ◽  
...  
Keyword(s):  
Surface Quality ◽  
Laser Scanning ◽  
Surface Defects ◽  
Rolled Strip ◽  
Environment Friendly ◽  
Lubrication Performance ◽  
Water Based ◽  
The Coefficient Of Friction ◽  
Water Base

In this research, the four-ball tribometer was examined to evaluate the tribological behavior of environment-friendly nano-MoS2 water-based rolling liquid. This experimental method is used to measure the maximum non-seizure load (PB) and the coefficient of friction (μ). The newly introduced parameter ω can be combined with PB and μ to evaluate the tribological performances of the rolling liquid comprehensively. The rolling lubrication performance of nano-MoS2 water-base lubricant was investigated using a single stand 4-high reversing rolling mill. The surface morphologies and rolling textures of the samples were measured by laser scanning confocal microscope after cold rolling. The results show that when the concentration of nano-MoS2 is 0.4wt.%, the water-based rolling liquid has excellent tribological and lubricating properties. Meanwhile, compared with the surface quality of the rolled strip under other lubrication conditions, the surface quality of the cold-rolled strip using 0.4wt% nano-MoS2 rolling liquid as the lubrication condition is smooth without visible surface defects.

Design of Automatic Detection Device for Steel Bar Surface Defects

2012 ◽  
Vol 532-533 ◽  
pp. 390-393 ◽  
Author(s):  
Jian Chuan Zhang ◽  
Wu Bin Li ◽  
Chang Hou Lu
Keyword(s):  
Image Processing ◽  
Surface Quality ◽  
Automatic System ◽  
Surface Defects ◽  
Detection System ◽  
High Luminance ◽  
Linear Ccd ◽  
Steel Bar ◽  
And Performance

To inspect the surface quality of steel bar, we designed an automatic system including linear camera and laser. Through the comparison among kinds of cameras, we select linear CCD to our system. The laser is also chosen by us with its high luminance and performance. Through a series of computation, we select the appropriate camera lens to our device. At last, we draw the whole detection system. This device has been used well and provides a good foundation for prospective image processing.

Study on the Influence of Amplitude on Ultrasonic Assisted Grinding of Hard and Brittle Materials

2021 ◽  
Vol 1047 ◽  
pp. 57-61
Author(s):  
Xiao Zhou Li ◽  
Bin Dai ◽  
Jin Kai Xu ◽  
Le Tong ◽  
Mao Xun Wang ◽  
...  
Keyword(s):  
Composite Materials ◽  
Surface Quality ◽  
Ultrasonic Vibration ◽  
Matrix Composite ◽  
Ceramic Matrix Composite ◽  
Ceramic Matrix ◽  
Grinding Force ◽  
High Tech ◽  
Grinding Process

With the development of advanced manufacturing technology, ceramic matrix composite materials, a typically hard and brittle material, have been widely used in high-tech fields such as aerospace manufacturing. Due to the anisotropy of materials, the quality of conventional processing workpieces is poor, and the processing accuracy is difficult to guarantee. In this experiment, ceramic matrix composite materials are machined by ultrasonic vibration grinding with the CBN grinding rods. The influence of amplitude on the grinding force and the surface quality of the workpiece in the grinding process are analyzed by a series of experiments on ceramic matrix composites. The results show that, compared with the conventional grinding process, in the ultrasonic vibration-assisted grinding process, the grinding force is reduced by about 60%, and the surface quality is also improved significantly,the surface roughness Sa is reduced by about 25%.

scholarly journals Experimental Research on the Surface Quality of Milling Contour Bevel Gears

2021 ◽  
Author(s):  
Mingyang Wu ◽  
Jianyu Zhang ◽  
Chunjie Ma ◽  
Yali Zhang ◽  
Yaonan Cheng
Keyword(s):  
Surface Roughness ◽  
Surface Quality ◽  
Surface Defects ◽  
Low Noise ◽  
Tooth Surface ◽  
Machining Accuracy ◽  
Machined Surface ◽  
Bevel Gears ◽  
Machined Surface Roughness

Abstract Contour bevel gears have the advantages of high coincidence, low noise and large bearing capacity, which are widely used in automobile manufacturing, shipbuilding and construction machinery. However, the quality of the tooth surface has a significant impact on the transmission accuracy of the gear, so it is of great significance to optimize the surface quality of the contour bevel gear. This paper firstly analyzes the formation process of machined surface roughness of contour bevel gears on the basis of generating machining method, and dry milling experiments of contour bevel gears are conducted to analyze the effects of cutting speed and feed rate on the machined surface roughness and surface topography of the workpiece. Then, the surface defects on the machined surface of the workpiece are studied by SEM, and the causes of the surface defects are analyzed by EDS. After that, XRD is used to compare the microscopic grains of the machined surface and the substrate material for diffraction peak analysis, and the effect of cutting parameters on the microhardness of the workpiece machined surface is investigated by work hardening experiment. The research results are of great significant for improving the machining accuracy of contour bevel gears, reducing friction losses and improving transmission efficiency.

Sign in / Sign up

Export Citation Format

Share Document