Optimization of Jet Parameters for Minimizing Surface Roughness in Cryogenic Milling of Ti-6Al-4V

2020 ◽  
Vol 143 (5) ◽  
Author(s):  
Yongqing Wang ◽  
Lingsheng Han ◽  
Kuo Liu ◽  
Yongquan Gan ◽  
Minghua Dai ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Liquid Nitrogen ◽  
Volume Fraction ◽  
Lower Surface ◽  
Internal Cooling ◽  
Cryogenic Machining ◽  
Gaseous Nitrogen ◽  
Cryogenic Milling ◽  
Influence Mechanism ◽  
Lower Volume

Abstract Cryogenic machining of titanium alloys using the internal cooling method is being identified as an alternative effective process to current practice of machining materials with poor thermal conductivity. The choice of jet parameters is particularly important for improving their machining quality and saving the production cost simultaneously. This research aimed to minimize the surface roughness by optimizing the comprehensive jet parameters in cryogenic milling Ti-6Al-4V. By comparing the cooling capability of liquid nitrogen and gaseous nitrogen, the influence mechanism of nitrogen phase on surface roughness was illuminated. A self-developed cryogenic machine tool with conveying liquid nitrogen through the spindle and tool was specially used to carry out milling experiments. The results indicated that the nitrogen phase had a most significant effect on surface roughness, followed by the pressure while the effect of flowrate was lowest. A lower volume fraction of gas, a higher pressure, and a proper flowrate could produce a lower surface roughness. An optimal combination of jet parameters was ultimately selected as the liquid nitrogen with 45 l/h of flowrate and 0.6 MPa of pressure to obtain the minimum surface roughness at 0.076 μm.

Effects of Liquid Nitrogen on Cryogenic Machining of Aisi D2 Hardened Steel

2011 ◽  
Vol 335-336 ◽  
pp. 400-405
Author(s):  
Samraj Ravi ◽  
Murugasan Pradeep Kumar
Keyword(s):  
Surface Roughness ◽  
Cutting Force ◽  
Liquid Nitrogen ◽  
Cutting Temperature ◽  
Hardened Steel ◽  
Cryogenic Machining ◽  
Workpiece Surface ◽  
Aisi D2 ◽  
Cutting Zone ◽  
Coated Carbide

The milling of hardened steel generates very high temperature in the cutting zone, and leads to detrimental effects on the cutting force, workpiece surface finish and tool life. Cryogenic machining is an environmental friendly new approach for the desirable control of the cutting temperature in the cutting zone. The present work investigates the effect of cryogenic cooling by liquid nitrogen (LN2) on the cutting temperature, cutting force and workpiece surface roughness on the end milling of AISI D2 steel by CVD TiN coated carbide insert, at a constant cutting speed of 100 m/min and varying feed rate in the range of 0.01-0.02 mm/tooth. The experimental results showed that with LN2 as a coolant the cutting force and workpiece surface roughness were reduced compared to dry and wet machining due to the better lubrication and cooling effect through reduction of cutting zone temperature.

scholarly journals Bonding and Thermal Cycling Performances of Two (Poly)Aryl–Ether–Ketone (PAEKs) Materials to an Acrylic Denture Base Resin

Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 543 ◽  
Author(s):  
Tzu-Yu Peng ◽  
Saiji Shimoe ◽  
Lih-Jyh Fuh ◽  
Chung-Kwei Lin ◽  
Dan-Jae Lin ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Thermal Cycling ◽  
Fatigue Testing ◽  
Lower Surface ◽  
Aryl Ether ◽  
Bonding Performance ◽  
Significant Difference ◽  
Aryl Ether Ketone ◽  
Ether Ketone ◽  
Thermal Cycling Fatigue

Poly(aryl–ether–ketone) materials (PAEKs) are gaining interest in everyday dental practices because of their natural properties. This study aims to analyze the bonding performance of PAEKs to a denture acrylic. Testing materials were pretreated by grinding, sandblasting, and priming prior to polymerization with the denture acrylic. The surface morphologies were observed using a scanning electron microscope and the surface roughness was measured using atomic force microscopy. The shear bond strength (SBS) values were determined after 0 and 2500 thermal cycles. The obtained data were analyzed using a paired samples t-test and Tukey’s honestly significant difference (HSD) test (α = 0.05). The surface characteristics of testing materials after different surface pretreatments showed obvious differences. PAEKs showed lower surface roughness values (0.02–0.03 MPa) than Co-Cr (0.16 MPa) and zirconia (0.22 MPa) after priming and sandblasting treatments (p < 0.05). The SBS values of PAEKs (7.60–8.38 MPa) met the clinical requirements suggested by ISO 10477 (5 MPa). Moreover, PAEKs showed significantly lower SBS reductions (p < 0.05) after thermal cycling fatigue testing compared to Co-Cr and zirconia. Bonding performance is essential for denture materials, and our results demonstrated that PAEKs possess good resistance to thermal cycling fatigue, which is an advantage in clinical applications. The results imply that PAEKs are potential alternative materials for the removable of prosthetic frameworks.

The Study on Microstructural and Optical Properties of Nanocrystalline Germanium Films

2010 ◽  
Vol 663-665 ◽  
pp. 324-327
Author(s):  
Chao Song ◽  
Rui Huang
Keyword(s):  
Multilayer Structure ◽  
Room Temperature ◽  
Multilayer Film ◽  
Volume Fraction ◽  
Raman Scattering Spectroscopy ◽  
Force Microscopy ◽  
Room Temperature Photoluminescence ◽  
Atomic Force ◽  
Lower Volume Fraction ◽  
Lower Volume

The germanium film and Ge/Si multilayer structure were fabricated by magnetron sputtering technique on silicon substrate at temperatures of 500°C. Raman scattering spectroscopy measurements reveal that the nanocrystalline Ge occurs in both kinds of samples. Furthermore, from the atomic force microscopy (AFM) results, it is found that the grain size as well as spatially ordering distribution of the nc-Ge can be modulated by the Ge/Si multilayer structure. The room temperature photoluminescence was also observed in the samples. However, compared with that from the nc-Ge film, the intensity of PL from the nc-Ge/a-Si multilayer film becomes weaker, which is attributed to its lower volume fraction of crystallized component.

Influence of Part Orientation on the Surface Roughness in the Process of Fused Deposition Modeling

2021 ◽  
Vol 896 ◽  
pp. 29-37
Author(s):  
Ján Milde ◽  
František Jurina ◽  
Jozef Peterka ◽  
Patrik Dobrovszký ◽  
Jakub Hrbál ◽  
...  
Keyword(s):  
Surface Roughness ◽  
3D Printing ◽  
Fused Deposition Modeling ◽  
Orientation Angle ◽  
Acrylonitrile Butadiene Styrene ◽  
Lower Surface ◽  
Geometrical Model ◽  
Fused Deposition ◽  
Deposition Modeling ◽  
Part Orientation

The article focused on the influence of part orientation on the surface roughness of cuboid parts during the process of fabricating by FDM technology. The components, in this case, is simple cuboid part with the dimensions 15 mm x 15mm x 30 mm. A geometrical model is defined that considers the shape of the material filaments after deposition, to define a theoretical roughness profile, for a certain print orientation angle. Five different print orientations in the X-axis of the cuboid part were set: 0°, 30°, 45°, 60°, and 90°. According to previous research in the field of FDM technology by the author, the internal structure (infill) was set at the value of 70%. The method of 3D printing was the Fused Deposition Modeling (FDM) and the material used in this research was thermoplastic ABS (Acrylonitrile butadiene styrene). For each setting, there were five specimens (twenty five prints in total). Prints were fabricated on a Zortrax M200 3D printer. After the 3D printing, the surface “A” was investigated by portable surface roughness tester Mitutoyo SJ-210. Surface roughness in the article is shown in the form of graphs (Fig.7). Results show increase in part roughness with increasing degree of part orientation. When the direction of applied layers on the measured surface was horizontal, significant improvement in surface roughness was observed. Findings in this paper can be taken into consideration when designing parts, as they can contribute in achieving lower surface roughness values.

scholarly journals Surface roughness of edge glued panels (EGP) of amazon maneged species

2019 ◽  
Vol 43 ◽  
Author(s):  
Roberto Daniel de Araujo ◽  
Joaquim dos Santos ◽  
Claudete Catanhede do Nascimento ◽  
Cristiano Souza do Nascimento ◽  
Sâmia Valeria dos Santos Barros ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Surface Quality ◽  
Sustainable Use ◽  
Lower Surface ◽  
Mechanical Tests ◽  
Important Criterion ◽  
Machining Performance ◽  
Technological Research ◽  
Tool Condition ◽  
Industrial Use

ABSTRACT In the Amazon, the sustainable use of wood is associated with technological research that indicates industrial use. Surface roughness of wood is an important criterion for assessing tool condition, machining performance and product quality. The objective of this study was to evaluate the surface roughness of five Amazonian woods used in the manufacture of EGP (Edge Glued Panels).The woods Angelim pedra, Angelim vermelho, Breu vermelho, Murici and Piãozinho, obtained from managed areas of the Amazon, were used in the manufacture of EGP panels. Surface treatments were performed with 120 and 180 grit sandpaper. Surface ripples (roughness) were measured using a digital roughness meter with needle (n = 180 readings). Physical and mechanical tests were performed on both wood and EGP samples, to verify the possible relationship between these properties and roughness. EGP Piãozinho presented better surface quality, which consists of lower roughness (lower surface wave height), while EGP Angelim pedra presented uneven surfaces. Surface quality was satisfactory when 120 grain sandpaper was applied to most products. The results showed a highly significant effect of roughness such as the physical-mechanical properties. The highlight of the study is the wood and EGP Piãozinho, because in all the tests, it always presented the best performances.

scholarly journals Effects of LaNiO3 Seed Layer on the Microstructure and Electrical Properties of Ferroelectric BZT/PZT/BZT Thin Films

2021 ◽  
Vol 8 ◽  
Author(s):  
Jinyu Ruan ◽  
Chao Yin ◽  
Tiandong Zhang ◽  
Hao Pan
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Surface Roughness ◽  
Electrical Properties ◽  
Seed Layer ◽  
Ferroelectric Properties ◽  
Lower Surface ◽  
Multilayer Films ◽  
Multilayer Thin Films ◽  
Orientation Growth

Ferroelectric multilayer films attract great attention for a wide variation of applications. The synergistic effect by combining different functional layers induces distinctive electrical properties. In this study, ferroelectric BaZr0.2Ti0.8O3/PbZr0.52Ti0.48O3/BaZr0.2Ti0.8O3 (BZT/PZT/BZT) multilayer thin films are designed and fabricated by using the magnetron sputtering method, and a LaNiO3 (LNO) seed layer is introduced. The microstructures and electrical properties of the BZT/PZT/BZT films with and without the LNO seed layer are systematically studied. The results show that the BZT/PZT/BZT/LNO thin film exhibits much lower surface roughness and a preferred (100)-orientation growth, with the growth template and tensile stress provided by the LNO layer. Moreover, an enhanced dielectric constant, decreased dielectric loss, and improved ferroelectric properties are achieved in BZT/PZT/BZT/LNO thin films. This work reveals that the seed layer can play an important role in improving the microstructure and properties of ferroelectric multilayer films.

scholarly journals Evaluation of the surface roughness of a nanofilled composite resin submitted to different smoothing and finishing techniques

2016 ◽  
Vol 45 (2) ◽  
pp. 110-114
Author(s):  
Micheli Del Frari ANSUJ ◽  
Iuri Silveira dos SANTOS ◽  
Marcela MARQUEZAN ◽  
Letícia Brandão DURAND ◽  
Roselaine Terezinha POZZOBON
Keyword(s):  
Surface Roughness ◽  
Composite Resin ◽  
Study Groups ◽  
Lower Surface ◽  
Control Group ◽  
Single Bond ◽  
Absolute Alcohol ◽  
Composite Resin Restorations ◽  
Level Of Significance ◽  
Surface Sealant

Abstract Introduction: Controlling the surface smoothness characteristics of the composite resin when performing a direct restorative technique is one of the factors involved in achieving restorative success. Objective: The purpose of this study was to evaluate the surface roughness of a nanofilled composite resin submitted to different smoothing and finishing techniques. Material and method: Fifty test specimens were made with the Z350 XT composite resin (3M ESPE) and then divided into five study groups according to the smoothing and finishing method applied, as follows: G1 (control), polyester strip; G2, composite spatula; G3, brush cleaned with absolute alcohol and dried; G4, brush cleaned with absolute alcohol, dried and moistened with Single Bond (3M ESPE); and G5, brush cleaned with absolute alcohol, dried and moistened with Natural Glaze surface sealant (DFL). After fabrication, the specimens were stored for 24 h in deionized water. The surface roughness of the specimens was measured using a profilometer. Surface roughness means were compared by analysis of variance followed by Tukey’s test at a level of significance of 5%. Result: The lowest surface roughness was observed in G1 (control group) and the highest, in G3. G5 had lower surface roughness values compared to the other test groups, and presented values similar to those of the control group. Conclusion: The smoothing and finishing techniques influenced the surface roughness of the composite resin. Application of the surface sealant by the copolymerization technique resulted in lower roughness values. The use of a clean, dry brush promoted roughness values beyond the acceptable limit, and is therefore liable to compromise the performance of composite resin restorations.

scholarly journals Tribological Behavior and Analysis on Surface Roughness of CNC Milled Dual Heat Treated Al6061 Composites

2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
A. Bovas Herbert Bejaxhin ◽  
G.M. Balamurugan ◽  
S.M. Sivagami ◽  
K. Ramkumar ◽  
V. Vijayan ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Surface Roughness ◽  
Lower Surface ◽  
Cnc Machining ◽  
Depth Of Cut ◽  
Good Surface ◽  
Heat Treated ◽  
Good Surface Finish ◽  
Artificial Neural Network Ann ◽  
Machining Properties

Dual heat treatment (DHT) effect is analyzed using the machining of Al6061-T6 alloy, a readily available material for quickly finding the machining properties. The heat treatments are conducted twice over the specimen by the furnace heating before processing through CNC machining. The HSS and WC milling cutters are preferred for the diameter of 10 mm for the reviewed rotational speeds of 2000 rpm and 4000 rpm, and the constant depth of cut of 0.5 mm is chosen based on various reviews. Worthy roughness could be provided mostly by the influence of feed rates preferred here as 0.05 mm/rev and 0.1 mm/rev. The influencing factors are identified by the Taguchi, genetic algorithm (GA), and Artificial Neural Network (ANN) techniques and compared within it. The simulation finding also helps to clarify the relationship between influenced machining constraints and roughness outcomes of this project. The average values of heat treated and nonheat treated Al6061-T6 are compared and it is to be evaluated that 41% improvement is obtained with the lower surface roughness of 1.78975 µm and it shows good surface finish with the help of dual heat treatment process.

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