Study on hole making process of thick-section CFRP

2021 ◽  
Author(s):  
Jianping Li ◽  
Anyuan Jiao ◽  
Xiaomei Chen
Keyword(s):  
Thick Section ◽  
Hole Making

scholarly journals Study on Hole Making Process of Thick-section Carbon Fiber Reinforced Plastics

2021 ◽  
Author(s):  
Jianping Li ◽  
Anyuan Jiao ◽  
Xiaomei Chen
Keyword(s):  
Carbon Fiber ◽  
Spindle Speed ◽  
Helical Milling ◽  
Thick Section ◽  
Fiber Reinforced ◽  
Influence Of Process Parameters ◽  
Variable Parameters ◽  
Hole Making ◽  
Carbon Fiber Reinforced

Abstract In this paper, the mechanism of helical milling was analyzed at first. Then, the orthogonal experiments on the 24mm thick carbon fiber reinforced composite material (CFRP) that affect the quality of hole making, such as spindle speed, feed per tooth, and number of tool’s blades were conducted. The influence of process parameters on the quality of hole making was analyzed. Finally, the range analysis method was used to obtain the best hole-making parameters: spindle speed is 4500rpm, feed per tooth is 0.02mm/z, the number of tool’s blades is 2. Based on the obtained optimal parameters, the step-by-step hole making of thick-section CFRP with variable parameters was studied, and two sets of parameters were designed. Through the measurement of the hole morphology, roughness, axial force and aperture deviation after the experiment, it is concluded that hole making process with variable parameters can meet the technical requirements of thick-section CFRP.

Methods for three-dimensional reconstruction of cellular components within a thick section

1986 ◽  
Vol 44 ◽  
pp. 18-21
Author(s):  
J. Frank ◽  
B. F. McEwen ◽  
M. Radermacher ◽  
C. L. Rieder
Keyword(s):  
Tilt Angle ◽  
Tomographic Reconstruction ◽  
3D Structure ◽  
Three Dimensional ◽  
Thick Section ◽  
Three Dimensional Reconstruction ◽  
Axis Ratio ◽  
Dimensional Reconstruction ◽  
Cellular Components

The tomographic reconstruction from multiple projections of cellular components, within a thick section, offers a way of visualizing and quantifying their three-dimensional (3D) structure. However, asymmetric objects require as many views from the widest tilt range as possible; otherwise the reconstruction may be uninterpretable. Even if not for geometric obstructions, the increasing pathway of electrons, as the tilt angle is increased, poses the ultimate upper limitation to the projection range. With the maximum tilt angle being fixed, the only way to improve the faithfulness of the reconstruction is by changing the mode of the tilting from single-axis to conical; a point within the object projected with a tilt angle of 60° and a full 360° azimuthal range is then reconstructed as a slightly elliptic (axis ratio 1.2 : 1) sphere.

scholarly journals Study of the effect of inter-pass temperature on weld overlap start-stop defects and mitigation by application of laser defocusing

2021 ◽  
Vol 114 (1-2) ◽  
pp. 117-130
Author(s):  
Wai Jun Lai ◽  
Supriyo Ganguly ◽  
Wojciech Suder
Keyword(s):  
Thermal Cycle ◽  
Laser Initiation ◽  
Thick Section ◽  
Keyhole Welding ◽  
Run Off ◽  
And Control ◽  
Laser Keyhole Welding

AbstractLaser keyhole initiation and termination-related defects, such as cracking and keyhole cavities due to keyhole collapse, are a well-known issue in laser keyhole welding of thick section steels. In longitudinal welding, run-on and run-off plates are used to avoid this problem. However, such an approach is not applicable in circumferential welding where start/stop defects remain within the workpiece. These issues can hinder industry from applying laser keyhole welding for circumferential welding applications. In this paper, the effect of inter-pass temperature on laser keyhole initiation and termination at the weld overlap start-stop region was investigated. This study has identified that defects occurring within this region were due to laser termination rather than laser initiation because of keyhole instabilities regardless of the thermal cycle. The laser termination defects were mitigated by applying a laser defocusing termination regime to reduce the keyhole depth gradually and control the closure of the keyhole.

On projected thick sections of stationary point processes and Boolean models

1996 ◽  
Vol 28 (2) ◽  
pp. 335-335
Author(s):  
Markus Kiderlen
Keyword(s):  
Point Process ◽  
Stationary Point ◽  
Point Processes ◽  
Linear Subspace ◽  
Isotropic Case ◽  
Thick Section ◽  
Boolean Models ◽  
Dimensional Linear Subspace ◽  
Stationary Point Process ◽  
Stationary Point Processes

For a stationary point process X of convex particles in ℝd the projected thick section process X(L) on a q-dimensional linear subspace L is considered. Formulae connecting geometric functionals, e.g. the quermass densities of X and X(L), are presented. They generalize the classical results of Miles (1976) and Davy (1976) which hold only in the isotropic case.

scholarly journals Detecting the normal-direction in automated aircraft manufacturing based on adaptive alignment

2020 ◽  
Vol 103 (4) ◽  
pp. 003685042098121
Author(s):  
Ying Zhang ◽  
Hongchang Ding ◽  
Changfu Zhao ◽  
Yigen Zhou ◽  
Guohua Cao
Keyword(s):  
Calibration Method ◽  
Adaptive Method ◽  
Normal Direction ◽  
Detection Accuracy ◽  
Average Deviation ◽  
Important Indicator ◽  
Aircraft Manufacturing ◽  
Direction Detection ◽  
Hole Making ◽  
Vertical Accuracy

In aircraft manufacturing, the vertical accuracy of connection holes is important indicator of the quality of holes making. Aircraft products have high requirements for the vertical accuracy of holes positions. When drilling and riveting are performed by an automatic robotic system, assembly errors, bumps, offsets and other adverse conditions, can affects the accuracy of manufacturing and detection, and in turn the fatigue performance of the entire structure. To solve this problem, we proposed a technology for detecting the normal-direction based on the adaptive alignment method, built a mathematical model for posture alignment, and studied the calibration method and mechanism of the detection device. Additionally, we investigated techniques for error compensation using an electronic theodolite and other devices when the adaptive method is used for detection. In verification experiments of the method, multiple sets of results demonstrated that the key technical indicators are as follows: normal accuracy <0.5°, average deviation after correction =0.0667°. This method can effectively compensate the errors affecting hole making work in automated manufacturing, and further improve the positioning accuracy and normal-direction detection accuracy of the robot.

Sign in / Sign up

Export Citation Format

Share Document