Effect of Waterjet Machining Parameters on the Cut Quality of PP and PVC-U Materials Coated with Polyurethane and Acrylate Coatings

The article focuses on the machining of polymeric materials polypropylene (PP) and un-plasticized poly vinyl chloride (PVC-U) after surface treatment with polyurethane and acrylate coatings using waterjet technology. Two types of waterjet technologies, abrasive waterjet (AWJ) and waterjet without abrasive (WJ), were used. The kerf width and its taper angle, at the inlet and outlet of the waterjet from the workpiece, were evaluated. Significant differences between AWJ and WJ technology were found. WJ technology proved to be less effective due to the creation of a nonuniform cutting gap and significant burrs. AWJ technology was shown to be more efficient, i.e., more uniform cuts were achieved compared to WJ technology, especially at a cutting head traverse speed of 50 mm·min−1. The most uniform kerf width or taper angle was achieved for PP + MOBIHEL (0.09°). The materials (PP and PVC-U) with the POLURAN coating had higher values of the taper angle of the cutting gap than the material with the MOBIHEL coating at all cutting head traverse speeds. The SEM results showed that the inappropriate cutting head traverse speed and the associated WJ technology resulted in significant destruction of the material to be cut on the underside of the cut. Delamination of the POLURAN and MOBIHEL coatings from the base material PP and PVC-U was not demonstrated by SEM analysis over the range of cutting head traverse speeds, i.e., 50 to 1000 mm·min−1.

GEOMETRY OF KERF WHEN CURVE SAWING WITH A CIRCULAR RIP-SAW

Rip-sawing following the curvature of a crooked log means advantages for yield. However, the possibility to saw in a narrow curve with a circular saw blade is limited because of the inherently flat geometry of circular saw blades. For a double arbour circular saw the situation is even more problematic because the two blades have a certain overlap and thus, the two arbours are not positioned in the same horizontal position. In this study, a theoretical geometrical study of the creation of a kerf with a single circular saw blade and with a double arbour circular saw with two saw blades was examined. Results for stiff saw blades show that the kerfs become in general curved and inclined (tilted) in the vertical direction and also that the width of the kerfs for double arbour saws becomes wider at the top and bottom of the cant than in the middle. Additionally, the sawn boards obtain varying thickness along their width because of the varying kerf width. A comparison with experimental thickness data from four test sawings at a sawmill indicates that the theoretical results are valid and that curve sawn boards become thinner than straight sawn boards.

MACHINABILITY ASSESSMENT OF SHAPE MEMORY ALLOY NITINOL DURING WEDM OPERATION: APPLICATION POTENTIAL OF TAGUCHI BASED AHP–DFA TECHNIQUE

This paper exemplifies the feasibility of expanding a multi-criteria decision-making (MCDM) method to select optimum process parameters during the wire electrical discharge machining (WEDM) of nitinol. The application potential of combined desirability function analysis (DFA) and analytical hierarchy process (AHP) has been reported. Nitinol, a shape memory alloy (SMA), can memorize or retain its original shape when subjected to thermo-mechanical or magnetic loads. Four key input variables, like pulse on time ([Formula: see text], pulse off time ([Formula: see text], wire tension (WT), and wire feed (WF) have been studied to optimize three correlated responses, like kerf width, material removal rate (MRR), and surface roughness ([Formula: see text]. Process parameter permutations [Formula: see text]s, [Formula: see text]s, [Formula: see text] kg-F and [Formula: see text][Formula: see text]m/min were found to yield the optimum results. For the desired kerf width, MRR and [Formula: see text], the optimum process parameters were also achieved expending Taguchi’s signal-to-noise ratio. Validation results affirmed that the MCDM approach, AHP–DFA is a proficient strategy to select optimal input parameters for a preferred output eminence for WEDM of nitinol.

Experimental study of mild steel cutting process by using the plasma arc method

Purpose: In this study, plasma arc cutting (PAC) is an industrial process widely used for cutting various away types of metals in several operating conditions. Design/methodology/approach: It is carried out a systematic or an authoritative inquiry to discover and examine the fact, the plasma cutting process is to establish the accuracy and the quality of the cut in this current paper assessed a good away to better the cutting process. Findings: It found that the effect of parameters on the cutting quality than on the results performed to accomplish by statistical analysis. Research limitations/implications: The objective of the present work paper is to achieve cutting parameters, thus the quality of the cutting process depends upon the plasma gas pressure, scanning speed, cutting power, and cutting height. Practical implications: The product of the plasma cutting process experimentally has been the quality of the cutting equipment that was installed to monitor kerf width quality by exam the edge roughness, kerf width, and the size of the heat-affected zone (HAZ). Originality/value: The results reveal that were technically possessed of including all the relevant characteristics, then a quality control for the cutting and describe the consequence of the process parameters.

Studies of kerf width and surface roughness using the response surface methodology in AA 4032–TiC composites

A substantially developed machining process, namely wire electrical discharge machining (WEDM), is used to machine complex shapes with high accuracy. This existent work investigates the optimization of the process parameters of wire electrical discharge machining, such as pulse on time ( Ton), peak current ( I), and gap voltage ( V), to analyze the output performance, such as kerf width and surface roughness, of AA 4032–TiC metal matrix composite using response surface methodology. The metal matrix composite was developed by handling the stir casting system. Response surface methodology is implemented through the Box–Behnken design to reduce experiments and design a mathematical model for the responses. The Box–Behnken design was conducted at a confident level of 99.5%, and a mathematical model was established for the responses, especially kerf width and surface roughness. Analysis of variance table was demarcated to check the cogency of the established model and determine the significant process. Surface roughness attains a maximum value at a high peak current value because high thermal energy was released, leading to poor surface finish. A validation test was directed between the predicted value and the actual value; however, the deviation is insignificant. Moreover, a confirmation test was handled for predicted and experimental values, and a minimal error was 2.3% and 2.12% for kerf width and surface roughness, respectively. Furthermore, the size of the crater, globules, microvoids, and microcracks were increased by amplifying the pulse on time.