Qualitative Analysis and Study the Workpiece Shearing Surface Quality of Fine-Blanking with Negative Clearance

2011 ◽  
Vol 697-698 ◽  
pp. 371-376
Author(s):  
Hong Du ◽  
Zhong Mei Zhang
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Qualitative Analysis ◽  
Surface Quality ◽  
Reference Value ◽  
Quality Standard ◽  
Fine Blanking ◽  
Negative Clearance ◽  
Scanning Electron

The workpieces of fine blanking with negative clearance were obtained through the fine-blanking with negative clearance processing experiment. The fractography photographs of workpieces shearing surface were scanned by scanning electron microscope (SEM), and the characterization parameters and quality standard of workpieces shearing surface with negative clearance were analyzed in the processing of blanking. According to the characterization parameters and quality standard of workpieces shearing surface with negative clearance, the workpiece with the length ratio of burnish band, deflection error, rollover error and blanking burr were analyzed qualitative. The findings have a certain reference value to the blanking related profession.

Study on the Process of Pure Shearing and Fracture for AISI-1020 and AISI-1045 Blanking with Negative Clearance

2010 ◽  
Vol 135 ◽  
pp. 215-219
Author(s):  
Wei Fu Fan ◽  
Jian Hua Li ◽  
Zhong Mei Zhang
Keyword(s):  
Experimental Data ◽  
Electron Microscope ◽  
Research Result ◽  
Reference Value ◽  
Work Piece ◽  
Fine Blanking ◽  
Aisi 1045 ◽  
Negative Clearance ◽  
Metallic Sheet ◽  
Scanning Electron

This paper carried through fine-blanking with negative clearance processing experiment with the AISI-1020 and AISI-1045 and obtained the work piece of fine blanking with negative clearance. The fractography photographs in the different deform regions of rollover zone, shearing band, fracture zone and under sheared surface were scanned by scanning electron microscope (SEM-JSM-6360LV). The research result indicates that the plastic flow of fine-blanking with negative clearance has been carried out to punch downspin, then jib at the place of allowance value, so that the length of work piece burnish band as much as possible to maximize and the length of the smooth shearing fracture could reach more than 90% thickness of the metallic sheet. Owing to the ejector negative direction blanking, the second burnish band could be formed in the process of ejecting and the work piece has no burr in the undermost sheared face. The place of fracture of fine-blanking with negative clearance has emerged into the middle of work piece, not into the sheared undermost. And the width of fracture band is very tiny, only 50-100 micron. The research result provides theoretic reference and the experimental data for the practice application. It has instructive significance and reference value to manufacturing application.

Observability of Very Thick Specimen by Using Transmission Scanning Electron Microscope

1971 ◽  
Vol 29 ◽  
pp. 26-27
Author(s):  
K. Shibatomi ◽  
T. Yamanoto ◽  
H. Koike
Keyword(s):  
Electron Microscope ◽  
Image Quality ◽  
Scanning Electron Microscope ◽  
Chromatic Aberration ◽  
Image Contrast ◽  
Objective Lens ◽  
Thick Specimen ◽  
Transmission Electron ◽  
Scanning Electron

In the observation of a thick specimen by means of a transmission electron microscope, the intensity of electrons passing through the objective lens aperture is greatly reduced. So that the image is almost invisible. In addition to this fact, it have been reported that a chromatic aberration causes the deterioration of the image contrast rather than that of the resolution. The scanning electron microscope is, however, capable of electrically amplifying the signal of the decreasing intensity, and also free from a chromatic aberration so that the deterioration of the image contrast due to the aberration can be prevented. The electrical improvement of the image quality can be carried out by using the fascionating features of the SEM, that is, the amplification of a weak in-put signal forming the image and the descriminating action of the heigh level signal of the background. This paper reports some of the experimental results about the thickness dependence of the observability and quality of the image in the case of the transmission SEM.

The Contrast Research of the Finite Element Simulation for Ordinary and Fine Blanking with Negative Clearance

2008 ◽  
Vol 575-578 ◽  
pp. 316-321 ◽  
Author(s):  
H. Du ◽  
S.M. Ding
Keyword(s):  
Experimental Data ◽  
Reference Value ◽  
Engineering Practice ◽  
Fine Blanking ◽  
Equipment Investment ◽  
Element Simulation ◽  
Negative Clearance ◽  
Material Energy ◽  
Blanking Process

This paper puts forward a negative clearance fine-blanking theory and its technique process, and introduces the technical processing of fine-blanking which can be used on ordinary punching machines. In this paper, computer simulation and the experimental study of negative clearance fine-blanking process are carried out. Thus the parameters of the force of blanking, the value of negative clearance are determined. The effect of fine-blanking quality was obtained, and the perfect rate of the blanking fracture achieves 90%. By comparing negative clearance precise blanking with conventional blanking, the following conclusions are drawn: 1. Blanking quality of negative clearance blanking is increased by 57% than that of conventional blanking. 2. The down surface of the work-pieces obtained by the conventional blanking processing have 0.2 - 0.5 mm longitudinal burrs, while the work-pieces obtained by the negative clearance blanking have no burrs. Thus the processing of clear away the burrs could be spared. And the manpower, the material, energy and the equipment investment are saved. The researching result provides theoretic reference and the experimental data for the engineering practice. It has instructive significance and reference value to engineering manufacturing.

The Determination and Application of the Point Spread Function in the Scanning Electron Microscope

2018 ◽  
Vol 24 (4) ◽  
pp. 396-405 ◽  
Author(s):  
Matthew D. Zotta ◽  
Mandy C. Nevins ◽  
Richard K. Hailstone ◽  
Eric Lifshin
Keyword(s):  
Spatial Distribution ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Beam Current ◽  
Beam Shape ◽  
Practical Applications ◽  
Energy Beam ◽  
Working Distance ◽  
Scanning Electron

AbstractA method is presented to determine the spatial distribution of electrons in the focused beam of a scanning electron microscope (SEM). Knowledge of the electron distribution is valuable for characterizing and monitoring SEM performance, as well as for modeling and simulation in computational scanning electron microscopy. Specifically, it can be used to characterize astigmatism as well as study the relationship between beam energy, beam current, working distance, and beam shape and size. In addition, knowledge of the distribution of electrons in the beam can be utilized with deconvolution methods to improve the resolution and quality of backscattered, secondary, and transmitted electron images obtained with thermionic, FEG, or Schottky source instruments. The proposed method represents an improvement over previous methods for determining the spatial distribution of electrons in an SEM beam. Several practical applications are presented.

Fabrication of Accurate Diamond - Metal Composite Cutting Blade by Electrotyping Method

2006 ◽  
Vol 304-305 ◽  
pp. 57-61
Author(s):  
L.L. Fang ◽  
Bing Lin Zhang ◽  
Ning Yao
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Ph Value ◽  
Photoemission Spectroscopy ◽  
Metal Composite ◽  
X Ray Diffraction ◽  
Electrolytic Solution ◽  
X Ray ◽  
Scanning Electron

In this paper, we report that the experimental results of fabricated diamond-metal composite film. Electrotyping method was used to deposit the thick film. During the deposition, low internal stress electrolytic solution, the electric current density of cathode, PH value, temperature, the distance between cathode and anode, the pretreatment of motherboard cathode were selected simultaneously. It was found that stirring strongly affected the quality of the film. Especially stirring velocity affected the distribution of diamond grains. Scanning electron microscope (SEM), X-ray photoemission spectroscopy (XPS) and X-ray diffraction (XRD) were used to measure the surface morphology, the crystal microstructure, diamond grains distribution and the chemical environment of the film.

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