scholarly journals Effect of surface roughness on ultrasonic inspection of electron beam melting ti‐6AL‐4V

2019 ◽  
Vol 3 (2) ◽  
pp. 131-141
Author(s):  
Evan Hanks ◽  
Anthony Palazotto ◽  
David Liu
Keyword(s):  
Surface Roughness ◽  
Electron Beam ◽  
New Technology ◽  
High Surface ◽  
Ultrasonic Inspection ◽  
Ultrasonic Waves ◽  
Aviation Industry ◽  
Sound Waves ◽  
Machined Surface ◽  
Content Type

Purpose Experimental research was conducted on the effects of surface roughness on ultrasonic non-destructive testing of electron beam melted (EBM) additively manufactured Ti-6Al-4V. Additive manufacturing (AM) is a developing technology with many potential benefits, but certain challenges posed by its use require further research before AM parts are viable for widespread use in the aviation industry. Possible applications of this new technology include aircraft battle damage repair (ABDR), small batch manufacturing to fill supply gaps and replacement for obsolete parts. This paper aims to assess the effectiveness of ultrasonic inspection in detecting manufactured flaws in EBM-manufactured Ti-6Al-4V. Additively manufactured EBM products have a high surface roughness in “as-manufactured” condition which is an artifact of the manufacturing process. The surface roughness is known to affect the results of ultrasonic inspections. Experimental data from this research demonstrate the ability of ultrasonic inspections to identify imbedded flaws as small as 0.51 mm at frequencies of 2.25, 5 and 10 MHz through a machined surface. Detection of flaws in higher surface roughness samples was increased at a frequency of 10 MHz opposed to both lower frequencies tested. Design/methodology/approach The approach is to incorporate ultrasonic waves to identify flaws in an additive manufactured specimen Findings A wave frequency of 10 MHz gave good results in finding flaws even with surface roughness present. Originality/value To the best of the authors’ knowledge, this was the first attempt that was able to identify small flaws using ultrasonic sound waves in which surface roughness was present.

IMPROVEMENT OF SURFACE ROUGHNESS DURING TURNING OF PRE-HEATED MILD STEEL USING VOICE ACTIVATED ULTRASONIC WAVES

2015 ◽  
Vol 76 (6) ◽  
Author(s):  
Anayet U Patwari ◽  
Mohammad Ahsan Habib ◽  
Md. S. I. Chowdhury ◽  
Afzal H. Neelav ◽  
Md. Sharfat Latif ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Mild Steel ◽  
Ultrasonic Waves ◽  
Great Promise ◽  
Hybrid Technique ◽  
Average Surface Roughness ◽  
Sound Waves ◽  
Turning Process ◽  
Machined Surface ◽  
Average Surface

Surface roughness represents the dimensional accuracy of the finished product and is one of the most important quality parameters of the finished product. For improvement of the surface quality several techniques like magnetic field, ultrasonic assisted turning and so on has been introduced. Ultrasonically Assisted Turning has been one of the techniques which showed great promise. It is a hybrid technique based on superimposition of ultrasonic vibration on a movement of a cutting tool in turning process. In this paper, a new technique using the concept of voice activated mode generated ultrasonic smart waves has been proposed and adopted with an aim to improve average surface roughness of the preheated machined surface of mild steel. Externally voice activated ultrasonic sound waves were applied during turning process of preheated mild steel and its effect on average surface roughness was studied. Experimentations were carried out under different ultrasonic frequencies to determine the surface roughness to the best degree possible. The experimental results showed significant improvements in surface roughness in preheated machined products. 

The effect of EBM process parameters upon surface roughness

2016 ◽  
Vol 22 (3) ◽  
pp. 495-503 ◽  
Author(s):  
Rebecca Klingvall Ek ◽  
Lars-Erik Rännar ◽  
Mikael Bäckstöm ◽  
Peter Carlsson
Keyword(s):  
Surface Roughness ◽  
Electron Beam ◽  
Surface Properties ◽  
Process Parameters ◽  
Electron Beam Melting ◽  
Design Methodology ◽  
New Materials ◽  
Content Type ◽  
Melt Pool ◽  
Practical Implications

Purpose The surface roughness of products manufactured using the additive manufacturing (AM) technology of electron beam melting (EBM) has a special characteristic. Different product applications can demand rougher or finer surface structure, so the purpose of this study is to investigate the process parameters of EBM to find out how they affect surface roughness. Design/methodology/approach EBM uses metal powder to manufacture metal parts. A design of experiment plan was used to describe the effects of the process parameters on the average surface roughness of vertical surfaces. Findings The most important electron beam setting for surface roughness, according to this study, is a combination of “speed and current” in the contours. The second most important parameter is “contour offset”. The interaction between the “number of contours” and “contour offset” also appears to be important, as it shows a much higher probability of being active than any other interaction. The results show that the “line offset” is not important when using contours. Research limitations/implications This study examined “contour offset”, “number of contours”, “speed in combination with current” and “line offset”, which are process parameters controlling the electron beam. Practical implications The surface properties could have an impact on the product’s performance. A reduction in surface processing will not only save time and money but also reduce the environmental impact. Originality/value Surface properties are important for many products. New themes containing process parameters have to be developed when introducing new materials to EBM manufacturing. During this process, it is very important to understand how the electron beam affects the melt pool.

Research on Surface Topography and Roughness of Micro Parts by High Speed Turn-Milling

2014 ◽  
Vol 800-801 ◽  
pp. 607-612 ◽  
Author(s):  
Cheng Zhe Jin ◽  
Rui Fang
Keyword(s):  
Surface Roughness ◽  
Surface Topography ◽  
High Speed ◽  
Orthogonal Experiment ◽  
High Surface ◽  
Cutting Speed ◽  
Machined Surface ◽  
High Surface Quality ◽  
Micro Parts ◽  
Turn Milling

High speed turn-milling has superiority on the productivity and the quality of work pieces, and is more suitable to machine micro-shaft parts and desirable miniature parts based on the turn-milling technology. In this papers adopting orthogonal experiment method cutting experiments of orthogonal turn-milling Aluminum alloy have been done. The relation between turn-milling regimes (cutter rotate speed, axial feed, feed per tooth etc.) and machined surface roughness has been ascertained. Finally, primary and secondary order of cutting regimes impacting surface roughness has more been confirmed through orthogonal experiments variance analysis, the rotate speed of cutter (cutting speed) influence greatly on surface roughness. Through 2-dimension surface topography diagram and 3-dimension surface topography of processed surface, it can be seen that high speed turn-milling processing technology can process micro miniature component of high surface quality, and features excellent development prospect and application value.

Effect of processing parameters of electron beam melting machine on properties of Ti-6Al-4V parts

2016 ◽  
Vol 22 (3) ◽  
pp. 609-620 ◽  
Author(s):  
Dana H. Abdeen ◽  
Bruce R. Palmer
Keyword(s):  
Surface Roughness ◽  
Electron Beam ◽  
Process Parameters ◽  
Electron Beam Melting ◽  
Processing Parameters ◽  
Beam Current ◽  
Exterior Surface ◽  
Content Type ◽  
Critical Pitting Temperature ◽  
Model Equations

Purpose This paper aims to study the effect of processing parameters of an electron beam melting (EBM) machine on the surface roughness, critical pitting temperature and density of Ti-6Al-4V parts produced from the EBM machine. Design/methodology/approach In this study, statistically designed experiments were used to manufacture Ti-6Al-4V samples in the EBM machine under different process parameters of beam current, beam speed and offset focus. Surface roughness was measured for as-built samples using a 3D profilometer. Then, a potentiostatic test was conducted under 2.40 V vs saturated calomel electrode to determine the critical pitting temperature (CPT) in 3.5 per cent mass NaCl solution for the samples of different processing parameters. Next, density was measured for these samples. Finally, model equations were established to relate EBM’s process parameters to measured properties of surface roughness, CPT and density. Findings Results showed that offset focus had the main influence on surface roughness more than the beam current and the beam speed. Changing processing parameters did not affect corrosion behavior of EBM Ti-6Al-4V as CPT did not vary widely, although a slight effect on CPT values obtained from the beam current and the beam speed. Density was greatly affected by the offset focus more than the other parameters. It can be concluded that uniform and precise measurements of roughness and density are not achievable through this machine; only a range of these properties can be attained. Originality/value EBM machine produces 3D parts in a layer-based building process under high temperature and vacuum atmosphere. Due to the manufacturing technique and conditions, the resulting object has irregularities on the exterior surface and voids that are formed within the part, both of which affect samples’ properties like surface roughness, CPT and density. This study established model equations that can relate parts’ properties to processing parameters so that parts of specific properties are obtained to fit the application they are used for. For each property, ANOVA fits vs linear energy were also obtained.

Unsettled Topics on Surface Finishing of Metallic Powder Bed Fusion Parts in the Mobility Industry

2021 ◽  
Author(s):  
Kevin Slattery ◽  
Keyword(s):  
Surface Roughness ◽  
Electron Beam ◽  
High Surface ◽  
Metallic Powder ◽  
Surface Finishing ◽  
Powder Bed Fusion ◽  
Powder Bed ◽  
Challenges And Opportunities ◽  
The Cost ◽  
Fatigue Corrosion

Laser and electron-beam powder bed fusion (PBF) additive manufacturing (AM) technology has transitioned from prototypes and tooling to production components in demanding fields such as medicine and aerospace. Some of these components have geometries that can only be made using AM. Initial applications either take advantage of the relatively high surface roughness of metal PBF parts, or they are in fatigue, corrosion, or flow environments where surface roughness does not impose performance penalties. To move to the next levels of performance, the surfaces of laser and electron-beam PBF components will need to be smoother than the current as-printed surfaces. This will also have to be achieve on increasingly more complex geometries without significantly increasing the cost of the final component. Unsettled Topics on Surface Finishing of Metallic Powder Bed Fusion Parts in the Mobility Industry addresses the challenges and opportunities of this technology, and what remains to be agreed upon by the industry.

Identification of Residual Stress in the Production of Molding Tools by Turn-Milling Technology

2017 ◽  
Vol 14 (1) ◽  
pp. 14-16
Author(s):  
Michal Šajgalík ◽  
Tomáš Pavlusík ◽  
Jozef Pilc ◽  
Matej Mikloš ◽  
Igor Daniš ◽  
...  
Keyword(s):  
Residual Stress ◽  
Machine Tools ◽  
Tool Path ◽  
New Technology ◽  
High Surface ◽  
Heavy Duty ◽  
Machined Surface ◽  
Turn Milling ◽  
New Machine

Abstract This article describes how to plan the tool path and analyze the surface of the machined part by working simultaneously on two basic operations such as milling and turning. New machine tools allow parallel processing of both multi-axis tools at the same time, it is a production technology in which the workpiece and the tool are simultaneously rotating. This relatively new turnmilling technology could be an alternative to increasing productivity in many applications. Especially in cases involving heavy-duty materials or large diameters of machined surface. The aim of this study is to explore this new technology, especially with regard to the increased precision and quality of the surface of the workpiece. Experimental results show that the combination of these two operations is suitable for precise machining of rotationally symmetrical workpieces with high surface finish.

Influence of milling toolpaths in machining of the turbine blade

2019 ◽  
Vol 91 (10) ◽  
pp. 1327-1339
Author(s):  
Seyedamin Jarolmasjed ◽  
Behnam Davoodi ◽  
Babak Pourebrahim Alamdari
Keyword(s):  
Surface Roughness ◽  
Tool Wear ◽  
Turbine Blade ◽  
Tool Life ◽  
Surface Texture ◽  
Turbine Blades ◽  
Measuring System ◽  
Machining Processes ◽  
Machined Surface ◽  
Content Type

Purpose The purpose of this paper is to machine the pressure surface of the turbine blade made of A286 iron-based superalloy by using four directions of raster strategy, including horizontal upward, horizontal downward, vertical upward and vertical downward, to achieve appropriate surface roughness and to investigate the tool wear in each strategy. Design/methodology/approach In this study, all cutting tests were performed by DAHLIH-MCV 1020 BA vertical 3-axis machining center with ball nose end mill. After milling by each strategy, according to the surface slope, the surface was divided into 27 meshes, and roughness of surface was studied and compared. Roughness measuring after machining was implemented by using portable Mahr ps1 roughness tester, and surface texture was photographed by CCD 100× optical zoom camera. Also, to measure tool flank wear in each strategy as an indication of tool life, the surface of workpiece was divided into four equal areas. The wear of the inserts was measured by ARCS vertical non-contact measuring system at the end of each area. Findings The results indicate that cutting directions and toolpath strategies have significant influence on tool wear and surface roughness in machining processes and that they can be taken into consideration individually as determinative parameters. In this case, the most uniform surface texture and the lowest surface roughness are obtained by using horizontal downward direction; in addition, abrasion is a dominant tool wear mechanism in all experiments, and tool wear in the horizontal downward is lower than other strategies. Practical implications Machining of turbine blades or other airfoil-shaped workpieces is quite common in manufacturing aerospace and aircraft products. The results of this research contribute to increasing quality of machined surface and tool life in machining of turbine blade. Originality/value This work proves the significance of milling strategies in machining of the turbine blade made of A286 superalloy and, consequently, exhibits the proper strategy in terms of surface roughness and tool life. Also, this work explains and elaborates the behavior of A286 superalloy in machining processes, which has not been studied much in recent research works.

scholarly journals On the Effect of Electron Beam Melted Ti6Al4V Part Orientations during Milling

Metals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1172
Author(s):  
Abdulmajeed Dabwan ◽  
Saqib Anwar ◽  
Ali M. Al-Samhan ◽  
Mustafa M. Nasr
Keyword(s):  
Surface Roughness ◽  
Electron Beam ◽  
Surface Morphology ◽  
Surface Quality ◽  
Cutting Speed ◽  
Chip Morphology ◽  
Depth Of Cut ◽  
Machining Parameters ◽  
Machined Surface ◽  
Radial Depth

The machining of the electron beam melting (EBM) produced parts is a challenging task because, upon machining, different part orientations (EBM layers’ orientations) produce different surface quality even when the same machining parameters are employed. In this paper, the EBM fabricated parts are machined in three possible orientations with regard to the tool feed direction, where the three orientations are “tool movement in a layer plane” (TILP), “tool movement perpendicular to layer planes” (TLP), and “tool movement parallel to layers planes” (TPLP). The influence of the feed rate, radial depth of cut, and cutting speed is studied on surface roughness, cutting force, micro-hardness, microstructure, chip morphology, and surface morphology of Ti6Al4V, while considering the EBM part orientations. It was found that different orientations have different effects on the machined surface during milling. The results show that the EBM parts can achieve good surface quality and surface integrity when milled along the TLP orientation. For instance, surface roughness (Sa) can be improved up to 29% when the milling tool is fed along the TLP orientation compared to the other orientations (TILP and TPLP). Furthermore, surface morphology significantly improves with lower micro-pits, redeposited chips, and feed marks in case of the TLP orientation.

scholarly journals Optimising the process parameters of selective laser melting for the fabrication of Ti6Al4V alloy

2018 ◽  
Vol 24 (1) ◽  
pp. 150-159 ◽  
Author(s):  
Zhonghua Li ◽  
Ibrahim Kucukkoc ◽  
David Z. Zhang ◽  
Fei Liu
Keyword(s):  
Surface Roughness ◽  
Surface Quality ◽  
Selective Laser Melting ◽  
Process Parameters ◽  
High Surface ◽  
Optimum Process ◽  
Laser Melting ◽  
Vertical Side ◽  
Content Type

Purpose Surface roughness is an important evaluation index for industrial components, and it strongly depends on the processing parameters for selective laser molten Ti6Al4V parts. This paper aims to obtain an optimum selective laser melting (SLM) parameter set to improve the surface roughness of Ti6Al4V samples. Design/methodology/approach A response surface methodology (RSM)-based approach is proposed to improve the surface quality of selective laser molten Ti6Al4V parts and understand the relationship between the SLM process parameters and the surface roughness. The main SLM parameters (i.e. laser power, scan speed and hatch spacing) are optimized, and Ti6Al4V parts are manufactured by the SLM technology with no post processes. Findings Optimum process parameters were obtained using the RSM method to minimise the roughness of the top and vertical side surfaces. Obtained parameter sets were evaluated based on their productivity and surface quality performance. The validation tests have been performed, and the results verified the effectivity of the proposed technique. It was also shown that the top and vertical sides must be handled together to obtain better top surface quality. Practical implications The obtained optimum SLM parameter set can be used in the manufacturing of Ti6Al4V components with high surface roughness requirement. Originality/value RSM is used to analyse and determine the optimal combination of SLM parameters with the aim of improving the surface roughness quality of Ti6Al4V components, for the first time in the literature. Also, this is the first study which aims to simultaneously optimise the surface quality of top and vertical sides of titanium alloys.

Effect of melt parameters on density and surface roughness in electron beam melting of gamma titanium aluminide alloy

2017 ◽  
Vol 23 (3) ◽  
pp. 474-485 ◽  
Author(s):  
Ashfaq Mohammad ◽  
Abdurahman Mushabab Al-Ahmari ◽  
Abdullah AlFaify ◽  
Muneer Khan Mohammed
Keyword(s):  
Surface Roughness ◽  
Electron Beam ◽  
Additive Manufacturing ◽  
Titanium Aluminide ◽  
Electron Beam Melting ◽  
Tial Alloy ◽  
Gamma Titanium Aluminide ◽  
Content Type ◽  
Gamma Titanium ◽  
New Material

Purpose Electron beam melting (EBM) is one of the potential additive manufacturing technologies to fabricate aero-engine components from gamma titanium aluminide (γ-TiAl) alloys. When a new material system has to be taken in to the fold of EBM, which is a highly complex process, it is essential to understand the effect of process parameters on the final quality of parts. This paper aims to understand the effect of melting parameters on top surface quality and density of EBM manufactured parts. This investigation would accelerate EBM process development for newer alloys. Design/methodology/approach Central composite design approach was used to design the experiments. In total, 50 specimens were built in EBM with different melt theme settings. The parameters varied were surface temperature, beam current, beam focus offset, line offset and beam speed. Density and surface roughness were selected as responses in the qualifying step of the parts. After identifying the parameters which were statistically significant, possible reasons were analyzed from the perspective of the EBM process. Findings The internal porosity and surface roughness were correlated to the process settings. Important ones among the parameters are beam focus offset, line offset and beam speed. By jointly deciding the total amount of energy input for each layer, these three parameters played a critical role in internal flaw generation and surface evolution. Research limitations/implications The range selected for each parameter is applicable, in particular, to γ-TiAl alloy. For any other alloy, the settings range has to be suitably adapted depending on physical properties such as melting point, thermal conductivity and thermal expansion co-efficient. Practical implications This paper demonstrates how melt theme parameters have to be understood in the EBM process. By adopting a similar strategy, an optimum window of settings that give best consolidation of powder and better surface characteristics can be identified whenever a new material is being investigated for EBM. This work gives researchers insights into EBM process and speeds up EBM adoption by aerospace industry to produce critical engine parts from γ-TiAl alloy. Originality/value This work is one of the first attempts to systematically carry out a number of experiments and to evaluate the effect of melt parameters for producing γ-TiAl parts by the EBM process. Its conclusions would be of value to additive manufacturing researchers working on γ-TiAl by EBM process.

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