Journal of Materials and Manufacturing

Experimental evaluation of tool wear and surface roughness under different conditions in high-speed turning of Ti6Al4V alloy

2023-02-10T13:57:48+00:00

In high-speed machining of titanium alloys, due to their difficult-to-cut characteristics, tool life and surface quality are significantly affected by the generated large amount of heat in the cutting zone. High cutting speeds lead to more severe abrasion, adhesion, and diffusion wear mechanisms and thus, decrease tool life rapidly. Therefore, the application of an effective cooling/lubrication strategy is critical to improve tool performance and machined part quality. In this study, the effects of four different cooling/lubrication conditions (dry, conventional cutting fluid (CCF), minimum quantity lubrication (MQL), and cryogenic cooling) on tool wear and average surface roughness (Ra) in high-speed turning of Ti6Al4V alloy were investigated. Three cutting speeds (125, 250 and 350 m/min) were employed by keeping depth of cut (0.5 mm) and feed (0.1 mm) values constant. For each condition, the variations of flank and crater wears with cutting length were determined. According to test results, high speeds caused an increase in the cutting temperatures and this case also led to adhesive and abrasive wear mechanisms being effective simultaneously. Besides, the use of high speeds reduced the cooling/lubrication effects of cutting fluids. Due to the effective cooling and lubrication, lower Ra values were obtained under CCF conditions.

Parametric optimization and evaluating mechanical properties of poly lactic acid proceed by FDM additive manufacturing

2023-01-30T06:56:26+00:00

Additive manufacturing is emerging techniques for creating 3-D objects from a components design. The current work is focus on evaluating mechanical properties of PLA through Fused deposition modeling (FDM) techniques. The optimization was carried out by varying the printing process parameters such as printing speed (60 mm/s, 100 mm/s and 140 mm/s), layer thickness (0.1 mm, 0.2 mm, and 0.3 mm) and infill density (40%, 60%, and 80%). The impact of printing parameters on impact strength can be considered for the optimization process. The L9 orthogonal array is used to prepare the samples, and the Taguchi optimization method was used to optimize the process condition. Moreover current study includes an ANOVA of the measured data that determines the significant and assesses the total impact of each input parameters on response. The result shows that impact strength is observed to be higher at an infill density of 80%, a minimum layer thickness of 0.1 mm, and a printing speed of 100 Cº. Furthermore, ANOVA study shows that the order of the parameters that affected the impact strength was infill density followed by layer thickness and printing speed.

Experimental investigation of hole quality and chip analysis during the dry drilling process of Al6061-T6

2023-04-18T08:57:43+00:00

High-quality holes in the drilling process are possible by selecting appropriate cutting parameters, proper machine setup and tools. The current study examines how drilling parameters like spindle speed and feed rate affect the formation of chips as well as hole quality, including hole size, circularity, and surface roughness of Al6061-T6. HSS drill bits were used in dry drilling experiments. The results showed that hole size and circularity are increased with the high spindle speed and feed rate. While the high spindle speed and low feed rate result in low surface roughness. Analysis of variance indicates that the hole size was highly affected by feed rate, having a contribution of 61.58 % compared with spindle speed with a contribution of 36.12 %. Moreover, the contribution of feed rate on circularity is 69.30 % greater than the effect of spindle speed at 28.48 %. In contrast, the spindle speed has a high influence of 56.84 % on surface roughness, than the feed rate with 42.13 %. The outcome also demonstrated that short, segmented chips could be produced at low spindle speeds and high feed rates.

Experimental and statistical investigation of the effect of coating type on surface roughness, cutting temperature, vibration and noise in turning of mold steel

2023-04-26T11:48:33+00:00

In this study, machining experiments were performed by metal cutting in different cutting parameters with CVD (MT-TiCN + TiC +Al₂O₃ + TiN) and PVD (TiAIN) coated carbide tools NIMAX plastic mold steel in universal lathe. Changes in surface roughness, cutting temperature, vibration and noise that occurred during machining were examined. The test specimens were machined with 18 different parameters using three different cutting speeds (120, 160, 200 m / min) at three different feed rates (0.1, 0.15 and 0.2 mm / dev) and a constant depth of cut (0.6 mm). As a result of the experiments performed, surface roughness, cutting temperature, vibration and noise values were examined and the best performance was obtained with PVD coated cutting tool.

Fabrication and characterization of bio composite fiber boards from areca leaf sheaths

2023-05-30T13:03:13+00:00

Bio composite fiber boards were fabricated by utilizing the areca leaf sheaths. Areca leaf sheaths were obtained from areca nut tree and these leaf sheaths have fewer applications. Usually, these areca sheaths were decomposed in the soil without much utilization for practical applications. Bio composite fiber boards were fabricated by following the suitable methodology. The pulp consistency of the prepared pulp was determined by varying the different parameters. The pulp consistency of the fiber was found to be best suitable for manufacturing of bio composite medium-density fiber boards. The effect of NaOH on the fiber boards was also studied for different concentrations of NaOH and for the different soaking times. The density of the Bio composite fiber boards was studied by varying the different parameters during the fabrication methodology. Surface roughness (S_a) and Profile roughness (R_a) of the fabricated fiber boards were studied using NANOVEA ST400 USA-made 3D non-contact profilometer. It was found that the Surface Roughness value and Profile Roughness value of the fabricated materials are almost similar to the commercially available fiber sheets.