Yingbin Hu

Additive manufacturing of carbon fiber-reinforced plastic composites using fused deposition modeling: Effects of process parameters on tensile properties

Carbon fiber-reinforced plastic composites have been intensively used for many applications due to their attractive properties. The increasing demand of carbon fiber-reinforced plastic composites is driving novel manufacturing processes to be in short manufacturing cycle time and low production cost, which is difficult to realize during carbon fiber-reinforced plastic composites fabrication in common molding processes. Fused deposition modeling, as one of the additive manufacturing techniques, has been reported for fabricating carbon fiber-reinforced plastic composites. The process parameters used in fused deposition modeling of carbon fiber-reinforced plastic composites follow those in fused deposition modeling of pure plastic materials. After adding fiber reinforcements, it is crucial to investigate proper fused deposition modeling process parameters to ensure the quality of the carbon fiber-reinforced plastic parts fabricated by fused deposition modeling. However, there are no reported investigations on the effects of fused deposition modeling process parameters on the mechanical properties of carbon fiber-reinforced plastic composites. In the experimental investigations of this paper, carbon fiber-reinforced plastic composite parts are fabricated using a fused deposition modeling machine. Tensile tests are conducted to obtain the tensile properties. The effects of fused deposition modeling process parameters on the tensile properties of fused deposition modeling-fabricated carbon fiber-reinforced plastic composite parts are investigated. The fracture interfaces of the parts after tensile testing are observed by a scanning electron microscope to explain material failure modes and reasons.

Surface grinding of carbon fiber–reinforced plastic composites using rotary ultrasonic machining: Effects of tool variables:

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.

Surface grinding of CFRP composites using rotary ultrasonic machining: design of experiment on cutting force, torque and surface roughness

Carbon fiber reinforced plastic (CFRP) composites provide excellent properties, which make them attractive in many industries. However, due to the properties of high stiffness, anisotropy, and high abrasiveness of carbon fiber in CFRPs, they are regarded as difficult-to-cut materials. To find an efficient surface grinding process for CFRP, this paper conducts an investigation using RUM. Design of experiment (DOE) is vital to evaluate effects of input variables on output variables, and it could be used to obtain the optimal values of variables in such a process. DOE could also be used to decrease the test numbers, the research cost etc. However, there are no investigations on DOE in such a process. This investigation firstly tests the effects of three input variables, including tool rotation speed, feedrate, and ultrasonic power, on output variables, including cutting force, torque, and surface roughness, at two levels. This investigation will provide guides for future research.

Analytical modeling and experimental investigation of laser clad geometry

Abstract. Based on rapid prototyping and laser cladding, laser material deposition (LMD) can be used to produce a near-net shape component in which the deposition quality and geometry characteristics of the previous layer, especially the first layer, determines the deposition quality and process stability of LDM-ed parts. A theoretical model for the first deposition layer in the LMD process has been developed to estimate the clad geometry (width, depth, and height) depending on the process parameters (laser power, powder feed rate, and scanning speed). This model contains two constants that are calculated based on the experimental results. The theoretical results are discussed and compared with the experimental data from the perspective of mass energy and line mass. The theoretical results are in accordance with the experimental results with reasonable accuracy that indicates the capability of predicting the clad geometry.