scholarly journals Significant Reduction in Energy Consumption and Carbon Emission While Improving Productivity in Laser Drilling of CFRP Sheets with a Novel Stepped Process Parameter Parallel Ring Method

2022 ◽  
Vol 6 (1) ◽  
pp. 7
Author(s):  
Menghui Zhu ◽  
Chao Wei ◽  
Wei Guo ◽  
Zhizhou Zhang ◽  
Jinglei Ouyang ◽  
...  

Although laser drilling of carbon fibre-reinforced polymer (CFRP) composites offers the advantages of zero tool-wear and avoidance of fibre delamination compared with mechanical drilling, it consumes considerably more energy during the drilling process. This research shows that by using a new, stepped parameter parallel ring laser hole drilling method, an energy saving of 78.10% and an 18.37 gCO2 reduction for each hole, while improving productivity by more than 300%, can be achieved in laser drilling of 6 mm diameter holes in CFRP sheets of 2 mm in thickness, compared with previous laser drilling methods under the same drilling quality. The key reason for this is an increase in energy input to the inner rings enabling more rapid removal of the material, while the lower energy input for the outer ring provides a shielding trench to reduce the heat loss into the parent material. The results are compared with single-ring laser drilling and multiple-ring laser drilling with constant processing parameters, and a discussion is given on comparing with mechanical drilling and future prospects, including a combined mechanical drilling and laser pre-scribing process.

2006 ◽  
Vol 128 (3) ◽  
pp. 468-475 ◽  
Author(s):  
Hwa-Teng Lee ◽  
Joachim Mayer ◽  
Fu-Chuan Hsu ◽  
Werner P. Rehbach ◽  
Thomas Weirich ◽  
...  

This study adopts the application of the electrodischarge machining (EDM) hole-drilling method to the measurement of residual stress in AISI D2 cold work tool steel, AISI H13 hot work tool steel, and AISI 1045 medium carbon steel. A calibration procedure based on the thermal conductivity of the material is conducted to compensate for the additional compressive stress induced in the workpiece by the EDM hole-drilling operation. Since the formation of this white layer influences the magnitude of the induced stress, the scanning electron microscopy, transmission electron microscopy, and nanoindentation techniques are used to examine the microstructure and hardness of the white layer resolidified on the EDMed surface. The experimental results reveal that combination of the hole-drilling strain-gage method (ASTM standard E837) with an EDM drilling process provides the effective means of determining the residual stress in materials with high hardness and good wear resistance.


2012 ◽  
Vol 516 ◽  
pp. 54-59
Author(s):  
Keiji Ogawa ◽  
Heisaburo Nakagawa ◽  
Fumiya Murase ◽  
Susumu Nishida

This paper proposes a novel manufacturing process of a fine mesh filter screen with a pulsed laser. The fine mesh filter screen, made of stainless steel, has many small diameter holes with high aspect ratio and fine pitch. In the conventional process, an electron beam drills in a vacuum. However, this is very costly because of the expensive equipment required and batch process. Therefore, a laser drilling process for small diameter hole drilling in air with higher flexibility was proposed. The post-processes after the laser drilling completed the fine mesh filter screen.


Author(s):  
Rodrigo Blödorn ◽  
Mariana Tiemi Tamura ◽  
Rodrigo Alberto Henke ◽  
Matias Roberto Viotti ◽  
Armando Albertazzi Gonçalves Jr. ◽  
...  

Author(s):  
B S Yilbas ◽  
M Sami

Laser drilling may improve by proper selection of the laser parameters. One of the important parameters in laser hole drilling is the focus setting of the focusing lens. In the present study, the effect of the beam waist position on the resulting hole exit/entry diameter ratio is investigated experimentally. An Nd-YAG laser is used to drill the holes in stainless steel and mild steel sheets at different thicknesses. The study was conducted to include the physical processes involved at different beam waist positions during the drilling operations. It is shown that altering the beam waist positions tends to produce converging and diverging hole walls for negative and positive positions respectively. The drilling improves at a certain beam waist position for a given workpiece thickness.


2019 ◽  
Vol 3 (2) ◽  
pp. 111-118
Author(s):  
Bahtiar Wilantara ◽  
Raharjo Raharjo

This study aims to develop an analog compression tester measuring instrument into a digital compression tester as a measurement tool that can provide effectiveness and efficiency to users.                     This research is a research and development or R&D. This research was conducted in several steps, namely: problem identification, information gathering, product design, product manufacture, expert validation, product revision, testing, final production. The development of analog compression tester was first validated by material experts, media experts, and 15 students, and 5 students for field trials. The subjects of this study were vocational students at Taman Karya Madya Teknik Kebumen. Data collection techniques used in this study using instruments in the form of a questionnaire. The data analysis technique of this research is descriptive qualitative and quantitative descriptive percentage.                 The results of the development of digital compression tester designs are: 1) the tools and materials used are electric drill, grinding, cutter, goggles, gloves, masks, ruler, acetaminine welding, screwdriver, scissors, digital dial pressure gauge, hose, spark plugs, clamps , and nepel, 2) the manufacturing process that starts from the cutting process, the hole drilling process, the welding process and the process of connecting between components, 3) the workings of digital compression tester design that is reading the pressure or compression of the machine displayed on the monitor digitally using dial pressure digital gauge, 4) the test results obtained from the validation results from: a) material experts at 89% or Eligible; b) media experts at 85% or reasonable; c) response of field trial students in terms of ease of use and reading of 90% or feasible. Thus, the conclusion that the digital compression tester measuring instrument declared feasible to use for measurement.


2021 ◽  
Vol 3 (3) ◽  
Author(s):  
V. Chengal Reddy ◽  
Thota Keerthi ◽  
T. Nishkala ◽  
G. Maruthi Prasad Yadav

AbstractSurface roughness and heat-affected zone (HAZ) are the important features which influence the performance of the laser-drilled products. Understanding the influence of laser process parameters on these responses and identifying the cutting conditions for simultaneous optimization of these responses are a primary requirement in order to improve the laser drilling performance. Nevertheless, no such contribution has been made in the literature during laser drilling of AISI 303 material. The aim of the present work is to optimize the surface roughness (Ra) and HAZ in fibre laser drilling of AISI 303 material using Taguchi-based grey relational analysis (GRA). From the GRA methodology, the recommended optimum combination of process parameters is flushing pressure at 30 Pa, laser power at 2000 W and pulse frequency at 1500 Hz for simultaneous optimization of Ra and HAZ, respectively. From analysis of variance, the pulse frequency is identified as the most influenced process parameters on laser drilling process performance.


2020 ◽  
Vol 87 (12) ◽  
pp. 757-767
Author(s):  
Robert Wegert ◽  
Vinzenz Guski ◽  
Hans-Christian Möhring ◽  
Siegfried Schmauder

AbstractThe surface quality and the subsurface properties such as hardness, residual stresses and grain size of a drill hole are dependent on the cutting parameters of the single lip deep hole drilling process and therefore on the thermomechanical as-is state in the cutting zone and in the contact zone between the guide pads and the drill hole surface. In this contribution, the main objectives are the in-process measurement of the thermal as-is state in the subsurface of a drilling hole by means of thermocouples as well as the feed force and drilling torque evaluation. FE simulation results to verify the investigations and to predict the thermomechanical conditions in the cutting zone are presented as well. The work is part of an interdisciplinary research project in the framework of the priority program “Surface Conditioning in Machining Processes” (SPP 2086) of the German Research Foundation (DFG).This contribution provides an overview of the effects of cutting parameters, cooling lubrication and including wear on the thermal conditions in the subsurface and mechanical loads during this machining process. At first, a test set up for the in-process temperature measurement will be presented with the execution as well as the analysis of the resulting temperature, feed force and drilling torque during drilling a 42CrMo4 steel. Furthermore, the results of process simulations and the validation of this applied FE approach with measured quantities are presented.


Sign in / Sign up

Export Citation Format

Share Document