Abrasive waterjet machining of Ti/CFRP/Ti laminate and multi-objective optimization of the process parameters using response surface methodology

2019 ◽  
Vol 54 (13) ◽  
pp. 1741-1759 ◽  
Author(s):  
Dhiraj Kumar ◽  
Suhasini Gururaja

In present work, abrasive waterjet machining has been used to machine adhesively bonded titanium-carbon fiber-reinforced plastics-titanium hybrid laminate with varying traverse speed, jet pressure, and stand-off distance. The effect of varying abrasive waterjet machining parameters on cut quality has been quantified by material removal rate, metal composite interface damage factor, taper ratio ( T r), and surface roughness (Ra). Response surface methodology along with central composite design has been used to analyze the influence of process parameters on output responses. Additionally, analysis of variance was performed to identify the significant parameters on the output responses. For better abrasive waterjet cut quality, the optimal values of process parameters obtained were 200 MPa jet pressure, 237.693 mm/min traverse speed, and 1 mm stand-off distance. The corresponding material removal rate, metal composite interface damage factor, taper ratio, and surface roughness are 5.388 mm3/s, 1.41, 1.16, and 3.827 µm, respectively. Furthermore, validation tests have been performed with obtained optimal parameters that deliver satisfactory outcomes with an error of 5.35%, 3.07%, 2.29%, and 0.39% for material removal rate, metal composite interface damage factor, taper ratio, and surface roughness, respectively.

2021 ◽  
Vol 11 (11) ◽  
pp. 4925
Author(s):  
Jennifer Milaor Llanto ◽  
Majid Tolouei-Rad ◽  
Ana Vafadar ◽  
Muhammad Aamir

Abrasive water jet machining is a proficient alternative for cutting difficult-to-machine materials with complex geometries, such as austenitic stainless steel 304L (AISI304L). However, due to differences in machining responses for varied material conditions, the abrasive waterjet machining experiences challenges including kerf geometric inaccuracy and low material removal rate. In this study, an abrasive waterjet machining is employed to perform contour cutting of different profiles to investigate the impacts of traverse speed and material thickness in achieving lower kerf taper angle and higher material removal rate. Based on experimental investigation, a trend of decreasing the level of traverse speed and material thickness that results in minimum kerf taper angle values of 0.825° for machining curvature profile and 0.916° for line profiles has been observed. In addition, higher traverse speed and material thickness achieved higher material removal rate in cutting different curvature radii and lengths in line profiles with obtained values of 769.50 mm3/min and 751.5 mm3/min, accordingly. The analysis of variance revealed that material thickness had a significant impact on kerf taper angle and material removal rate, contributing within the range of 69–91% and 62–69%, respectively. In contrast, traverse speed was the least factor measuring within the range of 5–18% for kerf taper angle and 27–36% for material removal rate.


2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Prasad D. Unde ◽  
M. D. Gayakwad ◽  
N. G. Patil ◽  
R. S. Pawade ◽  
D. G. Thakur ◽  
...  

Abrasive waterjet machining (AWJM) is an emerging machining process in which the material removal takes place due to abrasion. A stream of abrasive particles mixed with filtered water is subjected to the work surface with high velocity. The present study is focused on the experimental research and evaluation of the abrasive waterjet machining process in order to evaluate the technological factors affecting the machining quality of CFRP laminate using response surface methodology. The standoff distance, feed rate, and jet pressure were found to affect kerf taper, delamination, material removal rate, and surface roughness. The material related parameter, orientation of fiber, has been also found to affect the machining performance. The kerf taper was found to be 0.029 for 45° fiber orientation whereas it was 0.036 and 0.038 for 60° and 90°, respectively. The material removal rate is 18.95 mm3/sec for 45° fiber orientation compared to 18.26 mm3/sec for 60° and 17.4 mm3/sec for 90° fiber orientation. The Ra value for 45° fiber orientation is 4.911 µm and for 60° and 90° fiber orientation it is 4.927 µm and 4.974 µm, respectively. Delamination factor is found to be more for 45° fiber orientation, that is, 2.238, but for 60° and 90° it is 2.029 and 2.196, respectively.


1997 ◽  
Vol 119 (4B) ◽  
pp. 776-785 ◽  
Author(s):  
R. Kovacevic ◽  
M. Hashish ◽  
R. Mohan ◽  
M. Ramulu ◽  
T. J. Kim ◽  
...  

Thermodynamic analysis of material removal mechanisms indicates that an ideal tool for shaping of materials is a high energy beam, having infinitely small cross-section, precisely controlled depth, and direction of penetration, and does not cause any detrimental effects on the generated surface. The production of the beam should be relatively inexpensive and environmentally sound while the material removal rate should be reasonably high for the process to be viable. A narrow stream of high energy water mixed with abrasive particles comes close to meeting these requirements because abrasive waterjet machining has become one of the leading manufacturing technologies in a relatively short period of time. This paper gives an overview of the basic research and development activities in the area of abrasive waterjet machining in the 1990s in the United States.


Author(s):  
Joseck Nyaporo Nyaboro ◽  
Mahmoud A. Ahmed ◽  
Hassan El-Hofy ◽  
Mohamed El-Hofy

Machining of hard-to-cut materials to a high degree of accuracy and surface quality is one of the most critical operations when fabricating different state-of-the-art engineered components. Abrasive waterjet machining (AWJM) is one of the non-conventional technologies, which is increasingly gaining a reputation for machining hard-to-cut materials. Despite many phenomenological investigations, the dynamic characteristics of the abrasive waterjet and physical interactions with the machined surface have not been thoroughly investigated in the context of understanding the machining process. The kerf geometry has been associated with several abrasive waterjet input parameters, but its characteristics have remained speculative among many researchers. In the present study, the governing equations of two-phase abrasive waterjet flow and the interaction with the material surface are developed and numerically simulated. With the help of precisely developed user-defined functions (UDF), the material removal process has been investigated. The dynamic jet characteristics and erosion rate are correlated to help characterize the kerf geometry. The proposed modelling approach is within the acceptable level of accuracy (< 5 %) when compared to experimental data. The results show that the jet dynamic characteristics and abrasive particle size significantly affect the kerf geometry and the material removal rate. The present findings not only provide a technical understanding of the AWJM process but also provide requisite guidelines in achieving high-precision machining of hard-to-cut materials.


2016 ◽  
Vol 10 (3) ◽  
pp. 392-400 ◽  
Author(s):  
M. Ramulu ◽  
◽  
Vara Isvilanonda ◽  
Rishi Pahuja ◽  
Mohamed Hashish ◽  
...  

High temperature Fiber Metal Laminate – Titanium/Graphite (Ti/Gr) is an advanced material system, developed to meet the high temperature requirements in aerospace applications. High specific strength and stiffness of composite core along with its protection from aggressive environment by tough titanium alloy sheets qualify FMLs for a promising alternative material where metallic and composites overcome each other's limitations. However, industrial employability of this three phase system is often limited by the machining challenges posed by the difference in material removal mechanisms of Titanium alloy, PIXA thermoplastic polyimide resin and graphite fibers. An experimental investigation was conducted to evaluate the machinability of 1 mm thick Ti/Gr laminate sheets through Abrasive Waterjet (AWJ) machining process in terms of kerf characteristics and material removal rate. The parametric influence of AWJ operating variables on machining performance was studied by systematically measuring operating variables (traverse speed and Abrasive flow rate) using fully crossed Design of experiment (DOE) scheme, and statistically analyzing using ANOVA (Analysis of variance) technique. Empirical models were developed to quantify these effects and predict the influence of process parameters on material removal rate, kerf taper, entry damage width and overcut in straight cutting of Ti/Gr sheets.


2009 ◽  
Vol 76-78 ◽  
pp. 357-362 ◽  
Author(s):  
Hong Tao Zhu ◽  
Chuan Zhen Huang ◽  
Jun Wang ◽  
Guo Qun Zhao ◽  
Quan Lai Li

The abrasive waterjet machining is a powerful tool in processing various materials, especially, for brittle materials, such as ceramic, glass and so on. However, the material removal of a brittle material when impacted by abrasive waterjet is not understood in detail. In this paper, the material removal model in fracture erosion of brittle materials by abrasive waterjet has been developed.


2011 ◽  
Vol 188 ◽  
pp. 733-738 ◽  
Author(s):  
Wu Sheng Luo ◽  
Cheng Yong Wang ◽  
Jun Wang ◽  
Y.X. Song

Erosion caused by solid particle impact is a very common phenomenon. In many fields such as particle (or slurry) transportation, equipment protection in a dust environment, turbine engineering, etc., prevention of particle erosion is the task. In other applications, it is used as a tool for desirable material removal, surface cleaning, controlled destruction, numerous studies on this subject have been conducted by researchers from many disciplines including physics, material science, mechanics, manufacturing, standardization, etc.. To provide a comprehensive view of the problem of erosion by solid particle impact, a review is conducted based on the literature collected on material subject of erosion by solid particle impact. The reviewed works are limited to ductile material erosion and four categories: erosion mechanism, parametric studies, material removal modeling and simulation modeling.


2013 ◽  
Vol 769 ◽  
pp. 77-84
Author(s):  
Karsten Flögel ◽  
Fabian Faltin

Titanium alloys offer outstanding properties with regard to its strength to density ratio and a good corrosive resistance in air atmospheres. Substantial advancements could be made by using titanium alloys, in particular for applications in the aerospace industry and medical engineering. However, no product innovation is possible without an appropriate machining technology. For example, low thermal conductivity and hot hardness lead to limitations regarding the applicable machining parameters, particularly for continuous cutting operations. Turning of high performance materials sets high demands on machine tools and especially on the used cutting tools. For conventional continuous cutting of titanium alloys the tool life time and therefore the tool life volume is limited due to the thermal mechanical behaviour. Depending on the chemical and structural composition of the alloy, conventional cutting operations can rarely be regarded as an economic solution. The Abrasive Waterjet Turning process (AWJT) represents a promising alternative manufacturing method to produce rotation-symmetrically or helical parts made of difficult to machine materials. The AWJT process combines the kinematics of conventional turning methods with process-specific advantages of the abrasive waterjet machining. The main advantages are the high variety of machinable materials, the long life time T of the focus nozzles of at least 300 minutes and its independence of the material to be processed. Furthermore, material-inhomogeneity or the initial geometrical contour of the workpiece cannot result in tool failures. An interaction of workpiece and tool known from conventional cutting processes cannot occur. An investigation on hyper eutectic aluminium alloys has shown that AWJT is an economic manufacturing process regarding the resulted material removal rates Qw and tool life volumes. The resulting roughnesses and roundnesses are comparable to a rough turning operation. In addition, AWJT results in a lower hardness penetration depth tw in comparison to conventional turning. Machining of titanium alloys with cylindrical and external turning operations as well as grooving is the next step in the experimental investigation of the machinability of difficult to machine materials with AWJT. Therefore, the objective of the presented work is to provide a model for predicting the material removal rate, the cylindrical roundness and the surface roughness of waterjet turning of the titanium alloy Ti6Al4V. In a screening experiment the significant setting parameters were identified and an adequate range of parameter settings for the response surface study was determined. The tested parameters were the feed rate vf, the abrasive flow rate m and particle size dp, the depth of cut dc and the rotational speed n of the workpiece. It is shown that in relation to the material removal rate Qw linear main effects as well as interaction effects are significant. The developed second-order-regression-model includes these linear main and interaction effects and the quadratic effects of the relevant setting parameters. Furthermore, the achieved material removal rates, tool life volumes, cylindrical roundness and surface quality are used as target values. Additionally the changes like plastic deformations and grain damages in the rim zone were compared to conventional machined parts. Relating to the material removal rate Qw, up to 2.5 cm³/min could be achieved for AWJT at a maximum height of profile Rz below 100 microns. Furthermore, the investigation resulted in a maximum tool life volume of 750 cm³ at a given nozzle life time. The results show that AWJT can be used as an economic alternative manufacturing process for rough turning of titanium alloys.


1991 ◽  
Vol 113 (1) ◽  
pp. 29-37 ◽  
Author(s):  
M. Hashish

This paper discusses the factors that need to be considered when selecting the operational parameters for abrasive-waterjet (AWJ) machining. Machining applications such as cutting, milling, and turning are considered along with sample data. The effects of different AWJ parameters on both the functional performance of the AWJ system components and the material removal process are discussed. Factors for optimizing these parameters include hardware limitations, high-pressure-related phenomena, and the performance interaction among the different nozzle components. Due to the large number of parameters and factors involved in AWJ machining processes, significant improvements in performance may be obtained by optimizing these parameters.


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