Browsing by Author "Ning, Fuda (TTU)"
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Item Energy consumption and saving analysis for laser engineered net shaping of metal powders(2016) Liu, Zhichao (TTU); Ning, Fuda (TTU); Cong, Weilong (TTU); Jiang, Qiuhong (TTU); Li, Tao; Zhang, Hongchao (TTU); Zhou, Yingge (TTU)With the increasing awareness of environmental protection and sustainable manufacturing, the environmental impact of laser additive manufacturing (LAM) technology has been attracting more and more attention. Aiming to quantitatively analyze the energy consumption and extract possible ways to save energy during the LAM process, this investigation studies the effects of input variables including laser power, scanning speed, and powder feed rate on the overall energy consumption during the laser deposition processes. Considering microhardness as a standard quality, the energy consumption of unit deposition volume (ECUDV, in J/mm3) is proposed as a measure for the average applied energy of the fabricated metal part. The potential energy-saving benefits of the ultrasonic vibration-assisted laser engineering net shaping (LENS) process are also examined in this paper. The experimental results suggest that the theoretical and actual values of the energy consumption present different trends along with the same input variables. It is possible to reduce the energy consumption and, at the same time, maintain a good part quality and the optimal combination of the parameters referring to Inconel 718 as a material is laser power of 300 W, scanning speed of 8.47 mm/s and powder feed rate of 4 rpm. When the geometry shaping and microhardness are selected as evaluating criterions, American Iron and Steel Institute (AISI) 4140 powder will cause the largest energy consumption per unit volume. The ultrasonic vibration-assisted LENS process cannot only improve the clad quality, but can also decrease the energy consumption to a considerable extent.Item Feasibility Exploration of Superalloys for AISI 4140 Steel Repairing using Laser Engineered Net Shaping(2017) Liu, Zhichao (TTU); Cong, Weilong (TTU); Kim, Hoyeol (TTU); Ning, Fuda (TTU); Jiang, Qiuhong (TTU); Li, Tao; Zhang, Hong-chao (TTU); Zhou, Yingge (TTU)Due to high strength and ductility, AISI 4141 alloy steel is widely used in many industrial applications, such as gears and blades. When it is composed to harsh working environment, severe mechanical failures may happen. In order to save the high added value of the components, necessary repairing techniques are required to recover their functionality. Laser Engineered Net Shaping (LENS) is an innovative technology for metal parts repairing and rebuilding due to its metallurgical bonding and exhibit heat affected zone (HAZ). Compared to other repairing processes, LENS cannot only reduce the manufacturing time and cost, increase material utilization, but also provide an outstanding as-fabricated mechanical properties. Considering the compatibility and availability of powder materials, the selection of to-be-fabricated materials are important and decisive to the mechanical properties and the quality of the deposits. In this investigation, nickel-based and cobalt based superalloys are deposited onto AISI 4140 steel substrate using laser engineered net shaping (LENS) process to verify the feasibility of these superalloys for repairing of AISI 4140 workpieces. The micro-hardness, tensile strength, fracture and wear resistance are analyzed to testify the resistance of deformation, tension and anti-friction performance of deposited materials.Item Rotary Ultrasonic Surface Machining of CFRP Composites: A Comparison with Conventional Surface Grinding(2017) Ning, Fuda (TTU); Wang, Hui (TTU); Hu, Yingbin (TTU); Cong, Weilong (TTU); Zhang, Meng; Li, Yuzhou (TTU)Rotary ultrasonic machining (RUM), a hybrid nontraditional process technology combining ultrasonic machining and grinding, has been proven to be a promising method for hole making of CFRP. Due to its advanced capabilities, RUM has been further extendedly applied in surface machining: rotary ultrasonic surface machining (RUSM). Carbon fiber reinforced plastic (CFRP) composites have found extensive applications in areas such as aerospace, automotive, and sports due to their superior material properties. CFRP components are usually near net shaped after molding processes, however, additional surface machining is still required to generate the final dimensions and functional surfaces of the advanced CFRP components especially with three-dimensional features. However, the investigations on RUSM of CFRP are very limited and there are no reported studies on comparisons between RUSM and conventional surface grinding (CSG) of CFRP. In this paper, for the first time, a comparative study between these two processes of CFRP in the aspects of axial and infeed-directional cutting forces, torque, and surface roughness is conducted. In order to better understand the material removal differences between these two processes, the kinematic motions of the abrasive grains are also analyzed and compared.Item Surface grinding of carbon fiber-reinforced plastic composites using rotary ultrasonic machining: Effects of tool variables(2016) Wang, Hui (TTU); Ning, Fuda (TTU); Hu, Yingbin (TTU); Fernando, P. K.S.C.; Pei, Z. J.; Cong, Weilong (TTU)Carbon fiber-reinforced plastic composites have many superior properties, including low density, high strength-to-weight ratio, and good durability, which make them attractive in many industries. However, due to anisotropic properties, high stiffness, and high abrasiveness of carbon fibers in carbon fiber-reinforced plastic, high cutting force, high tool wear, and high surface roughness are always caused in conventional machining processes. This article reports an investigation using rotary ultrasonic machining in surface grinding of carbon fiber-reinforced plastic composites in order to develop an effective and high-quality surface grinding process. In rotary ultrasonic machining surface grinding of carbon fiber-reinforced plastic composites, tool selection is of great importance since tool variables will significantly affect output variables. In this work, the effects of tool variables, including abrasive size, abrasive concentration, number of slots, and tool end geometry, on machining performances, including the cutting force, torque, and surface roughness, are experimentally studied. The results show that lower cutting forces and torque are generated by the tool with higher abrasive size, lower abrasive concentration, and two slots. Lower surface roughness is generated by the tool with smaller abrasive size, smaller abrasive concentration, two slots, and convex end geometry. This investigation will provide guides for tool selections during rotary ultrasonic machining surface grinding of carbon fiber-reinforced plastic composites.Item Ultrasonic Vibration-Assisted Laser Engineered Net Shaping of Inconel 718 Parts: A Feasibility Study(2017) Ning, Fuda (TTU); Hu, Yingbin (TTU); Liu, Zhichao (TTU); Cong, Weilong (TTU); Li, Yuzhou (TTU); Wang, Xinlin (TTU)Laser engineered net shaping (LENS) has been applied as a key technology in direct manufacturing or repairing of high added- value metal parts. Recently, many investigations on LENS manufacturing of Inconel 718 parts have been conducted for potential applications of the aircraft turbine component manufacturing or repairing. However, fabrication defects such as pores, cavities, and heterogeneous microstructures always exist in the parts, affecting part qualities and mechanical properties. Therefore, it is crucial to LENS-manufacture Inconel 718 parts in a high-quality and high-efficiency way. Ultrasonic vibration has been introduced into various melting metal solidification processes for process improvements. However, there are no reported investigations on ultrasonic vibration-assisted (UV-A) LENS of Inconel 718 parts. In this paper, for the first time, UV-A LENS is proposed to reduce the fabrication defects of Inconel 718 parts. The experimental investigation is conducted to study the effects of ultrasonic vibration on microstructures and microhardness of the parts fabricated by UV-A LENS and LENS without ultrasonic vibration. The results showed that ultrasonic vibration could reduce the porosity, refine the microstructure with a smaller average grain size, and fragment the detrimental phase with a uniform distribution, thus enhancing the microhardness of the fabricated parts.