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Paul Compston - One of the best experts on this subject based on the ideXlab platform.
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the effect of Processing temperature on wedge peel strength of cf pa 6 laminates manufactured in a laser tape Placement Process
Composites Part A-applied Science and Manufacturing, 2019Co-Authors: Christopher Stokesgriffin, Paul Compston, A Kollmannsberger, K DrechslerAbstract:Abstract High-performance thermoplastics such as PEEK have been most commonly studied for thermoplastic ATP. Engineering thermoplastics such as PA 6 have comparatively low melt viscosities and different Processing behaviour. The effect of Processing temperature on the quality of CF/PA 6 laminates manufactured with a near-infrared laser ATP system is investigated. The inter-laminar bond strength is characterised by wedge peel tests on samples manufactured at different Process temperatures from 200 °C to 460 °C at a Placement rate of 100 mm/s. Thermal degradation of the polymer was investigated by DSC and DMA. Optical microscopy of cross-sections revealed significant squeeze-out of the matrix for Process temperatures exceeding 320 °C, corresponding with a rapid decrease of wedge peel strength. No significant thermophysical changes were detected for temperatures up to 380 °C. Reduction of wedge peel strength at high temperatures was attributed to matrix squeeze-out caused by the low melt viscosity of the polymer and not thermal degradation of the PA 6.
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Steel-CF/PA 6 hybrids manufactured by a laser tape Placement Process: Effect of first-ply Placement rate on lap shear strength for garnet blasted substrates
Procedia Manufacturing, 2019Co-Authors: Christopher Stokes-griffin, Andreas Kollmannsberger, Paul Compston, Klaus DrechslerAbstract:Abstract This paper investigates the manufacture of selectively reinforced metal/composite hybrids in a laser-assisted automated tape Placement Process. Unidirectional carbon fibre/PA 6 composite tapes were applied to 1.9 mm hot rolled steel substrates. The bonding of the first ply to the substrate is critical to the success of the metal-composite hybrid. This work investigates the effect of increasing the first-ply Placement rate for speeds of 25 mm/s, 50 mm/s and 100 mm/s. The steel substrates were pre-treated by garnet blasting and then coating with a 60 μm layer of PA 6. The garnet blasted surface texture was quantified using white light interferometry. The thermal history for bonding of the first ply was measured with fine wire thermocouples. The interfacial bond strength of the hybrid laminates was assessed by ASTM D 3165 lap shear tests. The lap shear strength increased to the highest value of 22.4 MPa at 50 mm/s. Analysis of the fracture surfaces and thermal history suggest that the lower strengths at 25 mm/s and 100 mm/s are due to lower adhesion of the PA 6 coating to the metal substrate, most probably due to lower levels of crystallization.
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Manufacture of steel–CF/PA6 hybrids in a laser tape Placement Process: Effect of first-ply Placement rate on thermal history and lap shear strength
Composites Part A-applied Science and Manufacturing, 2018Co-Authors: Christopher Stokes-griffin, Andreas Kollmannsberger, S. Ehard, Paul Compston, Klaus DrechslerAbstract:Abstract This paper investigates the manufacture of selectively reinforced metal/composite hybrids in a laser-assisted automated tape Placement Process. Carbon-fibre/PA6 composite tapes were applied to PA6-coated steel substrates. The bonding of the first-ply to the substrate is critical to the success of the hybrid; the effect of first-ply Placement rate was investigated for speeds of 25 mm/s, 50 mm/s, 100 mm/s. The interfacial bond strength of the hybrid laminates was determined by ASTM D 3165 lap shear tests. A 3D finite element thermal model was formulated to elucidate the thermal behaviour for increasing first-ply Placement rate. A method for increasing model efficiency was shown to significantly decrease the computational difficulty while maintaining solution accuracy. Raising the first-ply Placement rate from 25 mm/s to 100 mm/s resulted in a fourfold increase in lap shear strength with a maximum value of 22 MPa. The greater strength at higher speeds is attributed to improved synchronisation of the temperature and consolidation pressure history.
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manufacture of steel cf pa6 hybrids in a laser tape Placement Process effect of first ply Placement rate on thermal history and lap shear strength
Composites Part A-applied Science and Manufacturing, 2018Co-Authors: Christopher Stokesgriffin, Andreas Kollmannsberger, S. Ehard, Paul Compston, Klaus DrechslerAbstract:Abstract This paper investigates the manufacture of selectively reinforced metal/composite hybrids in a laser-assisted automated tape Placement Process. Carbon-fibre/PA6 composite tapes were applied to PA6-coated steel substrates. The bonding of the first-ply to the substrate is critical to the success of the hybrid; the effect of first-ply Placement rate was investigated for speeds of 25 mm/s, 50 mm/s, 100 mm/s. The interfacial bond strength of the hybrid laminates was determined by ASTM D 3165 lap shear tests. A 3D finite element thermal model was formulated to elucidate the thermal behaviour for increasing first-ply Placement rate. A method for increasing model efficiency was shown to significantly decrease the computational difficulty while maintaining solution accuracy. Raising the first-ply Placement rate from 25 mm/s to 100 mm/s resulted in a fourfold increase in lap shear strength with a maximum value of 22 MPa. The greater strength at higher speeds is attributed to improved synchronisation of the temperature and consolidation pressure history.
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A laser tape Placement Process for selective reinforcement of steel with CF/PA6 composites: Effects of surface preparation and laser angle
Materials and Design, 2017Co-Authors: S. Ehard, Andreas Kollmannsberger, Klaus Drechsler, Paul CompstonAbstract:This paper investigates the manufacture of selectively reinforced hybrid metal/composite laminates in a laser tape Placement Process. Unidirectionally reinforced carbon fibre/PA 6 composite tapes were applied to 2.0mm mild steel substrates. The effects of applying various surface treatments to the steel substrates were investigated including grit blasting and/or the addition of 60μm and 100μm PA 6 film coatings. The effect of the laser angle was also studied. The substrate surface was characterised by profilometry, SEM and optical absorptance. The interfacial bond strength of the hybrid laminates was determined by ASTM D 5868 lap shear tests. Placement onto PA 6 coated substrates was successful with lap shear strengths as high as 30.7MPa achieved for grit blasted substrates coated with a 100μm PA 6 film. The Process was found to have a low sensitivity to laser bias angle.
Christopher Stokesgriffin - One of the best experts on this subject based on the ideXlab platform.
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the effect of Processing temperature on wedge peel strength of cf pa 6 laminates manufactured in a laser tape Placement Process
Composites Part A-applied Science and Manufacturing, 2019Co-Authors: Christopher Stokesgriffin, Paul Compston, A Kollmannsberger, K DrechslerAbstract:Abstract High-performance thermoplastics such as PEEK have been most commonly studied for thermoplastic ATP. Engineering thermoplastics such as PA 6 have comparatively low melt viscosities and different Processing behaviour. The effect of Processing temperature on the quality of CF/PA 6 laminates manufactured with a near-infrared laser ATP system is investigated. The inter-laminar bond strength is characterised by wedge peel tests on samples manufactured at different Process temperatures from 200 °C to 460 °C at a Placement rate of 100 mm/s. Thermal degradation of the polymer was investigated by DSC and DMA. Optical microscopy of cross-sections revealed significant squeeze-out of the matrix for Process temperatures exceeding 320 °C, corresponding with a rapid decrease of wedge peel strength. No significant thermophysical changes were detected for temperatures up to 380 °C. Reduction of wedge peel strength at high temperatures was attributed to matrix squeeze-out caused by the low melt viscosity of the polymer and not thermal degradation of the PA 6.
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manufacture of steel cf pa6 hybrids in a laser tape Placement Process effect of first ply Placement rate on thermal history and lap shear strength
Composites Part A-applied Science and Manufacturing, 2018Co-Authors: Christopher Stokesgriffin, Andreas Kollmannsberger, S. Ehard, Paul Compston, Klaus DrechslerAbstract:Abstract This paper investigates the manufacture of selectively reinforced metal/composite hybrids in a laser-assisted automated tape Placement Process. Carbon-fibre/PA6 composite tapes were applied to PA6-coated steel substrates. The bonding of the first-ply to the substrate is critical to the success of the hybrid; the effect of first-ply Placement rate was investigated for speeds of 25 mm/s, 50 mm/s, 100 mm/s. The interfacial bond strength of the hybrid laminates was determined by ASTM D 3165 lap shear tests. A 3D finite element thermal model was formulated to elucidate the thermal behaviour for increasing first-ply Placement rate. A method for increasing model efficiency was shown to significantly decrease the computational difficulty while maintaining solution accuracy. Raising the first-ply Placement rate from 25 mm/s to 100 mm/s resulted in a fourfold increase in lap shear strength with a maximum value of 22 MPa. The greater strength at higher speeds is attributed to improved synchronisation of the temperature and consolidation pressure history.
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an inverse model for optimisation of laser heat flux distributions in an automated laser tape Placement Process for carbon fibre peek
Composites Part A-applied Science and Manufacturing, 2016Co-Authors: Christopher Stokesgriffin, Paul CompstonAbstract:Abstract High power diode lasers have enabled higher Placement rates to be achieved in automated tape Placement (ATP) of thermoplastic-based composite materials. Laser ATP heads in published literature employ homogeneous linear or rectangular laser spots, however a variety of solutions are available to produce customised irradiance profiles. No efforts to date have investigated what a more ideal heat flux profile would be for laser ATP in terms of length and distribution. This paper describes a method to determine the required laser heat flux profiles to achieve desired heating zone temperature profiles by means of an inverse thermal model. A bonding model was implemented to assess the performance of various heating zone temperature profiles for Placement at 400 mm/s. Short beam strengths from experimental trials (Stokes-Griffin and Compston, 2015) were used to validate the bonding model. A two-stepped heating profile was found to provide a good balance of increased strength with a small increase in power requirement.
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investigation of sub melt temperature bonding of carbon fibre peek in an automated laser tape Placement Process
Composites Part A-applied Science and Manufacturing, 2016Co-Authors: Christopher Stokesgriffin, Paul CompstonAbstract:Abstract Automated Placement of thermoplastic-based composite tape is a highly non-isothermal Process with temperature gradients often exceeding 1000 °C/s. Models for the Process often assume that bonding ceases below the melting point, however the extreme cooling rates combined with high Placement velocities can result in a highly amorphous polymer during consolidation. Bonding below the melting point is generally limited due to the presence of crystallites which impede reptation of the polymer molecules, however in the case of an amorphous state, autohesion should proceed. This paper investigates bonding of carbon-fibre(CF)/PEEK with experimental trials performed where sub-melting point temperatures occur at the nip point. The thermal history was recorded with thermocouples embedded in the substrate. Bond predictions are compared with experimental strengths determined by lap shear measurements. Bonding below the melting point was shown to occur, indicating the Processing window could be wider than previously estimated by bonding models, particularly for higher Placement rates.
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the effect of Processing temperature and Placement rate on the short beam strength of carbon fibre peek manufactured using a laser tape Placement Process
Composites Part A-applied Science and Manufacturing, 2015Co-Authors: Christopher Stokesgriffin, Paul CompstonAbstract:Abstract The ability of a modern near infra-red laser tape Placement system to produce high-quality laminates is investigated by performing short beam strength tests on samples manufactured at different Process temperatures from 400 °C to 600 °C at Placement rates of 100 mm/s and 400 mm/s. The temperature history in tape Placement is highly dynamic and the correlation between the Process control temperature, laser power and the consolidation temperature is not well understood. The complete temperature history was therefore estimated with a previously developed optical-thermal model and validated using long wave infra-red imaging. Short beam strengths equivalent to conventional manufacturing methods were found for Placement rates of 400 mm/s. Failure modes of the samples were elucidated by scanning electron microscopy of the fracture surfaces. Signs of degradation were observed on samples prepared with a 600 °C Process temperature at 100 mm/s, however none was evidenced at 400 mm/s for the same Process temperature.
Klaus Drechsler - One of the best experts on this subject based on the ideXlab platform.
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Steel-CF/PA 6 hybrids manufactured by a laser tape Placement Process: Effect of first-ply Placement rate on lap shear strength for garnet blasted substrates
Procedia Manufacturing, 2019Co-Authors: Christopher Stokes-griffin, Andreas Kollmannsberger, Paul Compston, Klaus DrechslerAbstract:Abstract This paper investigates the manufacture of selectively reinforced metal/composite hybrids in a laser-assisted automated tape Placement Process. Unidirectional carbon fibre/PA 6 composite tapes were applied to 1.9 mm hot rolled steel substrates. The bonding of the first ply to the substrate is critical to the success of the metal-composite hybrid. This work investigates the effect of increasing the first-ply Placement rate for speeds of 25 mm/s, 50 mm/s and 100 mm/s. The steel substrates were pre-treated by garnet blasting and then coating with a 60 μm layer of PA 6. The garnet blasted surface texture was quantified using white light interferometry. The thermal history for bonding of the first ply was measured with fine wire thermocouples. The interfacial bond strength of the hybrid laminates was assessed by ASTM D 3165 lap shear tests. The lap shear strength increased to the highest value of 22.4 MPa at 50 mm/s. Analysis of the fracture surfaces and thermal history suggest that the lower strengths at 25 mm/s and 100 mm/s are due to lower adhesion of the PA 6 coating to the metal substrate, most probably due to lower levels of crystallization.
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Manufacture of steel–CF/PA6 hybrids in a laser tape Placement Process: Effect of first-ply Placement rate on thermal history and lap shear strength
Composites Part A-applied Science and Manufacturing, 2018Co-Authors: Christopher Stokes-griffin, Andreas Kollmannsberger, S. Ehard, Paul Compston, Klaus DrechslerAbstract:Abstract This paper investigates the manufacture of selectively reinforced metal/composite hybrids in a laser-assisted automated tape Placement Process. Carbon-fibre/PA6 composite tapes were applied to PA6-coated steel substrates. The bonding of the first-ply to the substrate is critical to the success of the hybrid; the effect of first-ply Placement rate was investigated for speeds of 25 mm/s, 50 mm/s, 100 mm/s. The interfacial bond strength of the hybrid laminates was determined by ASTM D 3165 lap shear tests. A 3D finite element thermal model was formulated to elucidate the thermal behaviour for increasing first-ply Placement rate. A method for increasing model efficiency was shown to significantly decrease the computational difficulty while maintaining solution accuracy. Raising the first-ply Placement rate from 25 mm/s to 100 mm/s resulted in a fourfold increase in lap shear strength with a maximum value of 22 MPa. The greater strength at higher speeds is attributed to improved synchronisation of the temperature and consolidation pressure history.
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manufacture of steel cf pa6 hybrids in a laser tape Placement Process effect of first ply Placement rate on thermal history and lap shear strength
Composites Part A-applied Science and Manufacturing, 2018Co-Authors: Christopher Stokesgriffin, Andreas Kollmannsberger, S. Ehard, Paul Compston, Klaus DrechslerAbstract:Abstract This paper investigates the manufacture of selectively reinforced metal/composite hybrids in a laser-assisted automated tape Placement Process. Carbon-fibre/PA6 composite tapes were applied to PA6-coated steel substrates. The bonding of the first-ply to the substrate is critical to the success of the hybrid; the effect of first-ply Placement rate was investigated for speeds of 25 mm/s, 50 mm/s, 100 mm/s. The interfacial bond strength of the hybrid laminates was determined by ASTM D 3165 lap shear tests. A 3D finite element thermal model was formulated to elucidate the thermal behaviour for increasing first-ply Placement rate. A method for increasing model efficiency was shown to significantly decrease the computational difficulty while maintaining solution accuracy. Raising the first-ply Placement rate from 25 mm/s to 100 mm/s resulted in a fourfold increase in lap shear strength with a maximum value of 22 MPa. The greater strength at higher speeds is attributed to improved synchronisation of the temperature and consolidation pressure history.
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A laser tape Placement Process for selective reinforcement of steel with CF/PA6 composites: Effects of surface preparation and laser angle
Materials and Design, 2017Co-Authors: S. Ehard, Andreas Kollmannsberger, Klaus Drechsler, Paul CompstonAbstract:This paper investigates the manufacture of selectively reinforced hybrid metal/composite laminates in a laser tape Placement Process. Unidirectionally reinforced carbon fibre/PA 6 composite tapes were applied to 2.0mm mild steel substrates. The effects of applying various surface treatments to the steel substrates were investigated including grit blasting and/or the addition of 60μm and 100μm PA 6 film coatings. The effect of the laser angle was also studied. The substrate surface was characterised by profilometry, SEM and optical absorptance. The interfacial bond strength of the hybrid laminates was determined by ASTM D 5868 lap shear tests. Placement onto PA 6 coated substrates was successful with lap shear strengths as high as 30.7MPa achieved for grit blasted substrates coated with a 100μm PA 6 film. The Process was found to have a low sensitivity to laser bias angle.
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Simulation and experimental validation of gaps and bridging in the automated fiber Placement Process
Science and Engineering of Composite Materials, 2015Co-Authors: Roland Lichtinger, Javier Lacalle, Uwe Beier, Roland Hinterhölzl, Klaus DrechslerAbstract:With the increasing demand for carbon fiber-reinforced parts in the aerospace industry, automated manufacturing methods such as automated fiber Placement (AFP) are being established. To utilize AFP’s strong potential on multiple-curved surfaces such as chamfered sandwich structures, it is important to analyze and control emerging effects like gaps, bridging, and steering. An analytical relationship between path generation and effects of the AFP manufacture of chamfered sandwich structures have been found with good agreement to experimental tests. The deformation behavior of an industrially used compaction roller has been analyzed numerically and experimentally. The results show a nonuniform deformation behavior on flat and curved surfaces and the limited deformability of the compaction roller.
S. Ehard - One of the best experts on this subject based on the ideXlab platform.
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manufacture of steel cf pa6 hybrids in a laser tape Placement Process effect of first ply Placement rate on thermal history and lap shear strength
Composites Part A-applied Science and Manufacturing, 2018Co-Authors: Christopher Stokesgriffin, Andreas Kollmannsberger, S. Ehard, Paul Compston, Klaus DrechslerAbstract:Abstract This paper investigates the manufacture of selectively reinforced metal/composite hybrids in a laser-assisted automated tape Placement Process. Carbon-fibre/PA6 composite tapes were applied to PA6-coated steel substrates. The bonding of the first-ply to the substrate is critical to the success of the hybrid; the effect of first-ply Placement rate was investigated for speeds of 25 mm/s, 50 mm/s, 100 mm/s. The interfacial bond strength of the hybrid laminates was determined by ASTM D 3165 lap shear tests. A 3D finite element thermal model was formulated to elucidate the thermal behaviour for increasing first-ply Placement rate. A method for increasing model efficiency was shown to significantly decrease the computational difficulty while maintaining solution accuracy. Raising the first-ply Placement rate from 25 mm/s to 100 mm/s resulted in a fourfold increase in lap shear strength with a maximum value of 22 MPa. The greater strength at higher speeds is attributed to improved synchronisation of the temperature and consolidation pressure history.
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Manufacture of steel–CF/PA6 hybrids in a laser tape Placement Process: Effect of first-ply Placement rate on thermal history and lap shear strength
Composites Part A-applied Science and Manufacturing, 2018Co-Authors: Christopher Stokes-griffin, Andreas Kollmannsberger, S. Ehard, Paul Compston, Klaus DrechslerAbstract:Abstract This paper investigates the manufacture of selectively reinforced metal/composite hybrids in a laser-assisted automated tape Placement Process. Carbon-fibre/PA6 composite tapes were applied to PA6-coated steel substrates. The bonding of the first-ply to the substrate is critical to the success of the hybrid; the effect of first-ply Placement rate was investigated for speeds of 25 mm/s, 50 mm/s, 100 mm/s. The interfacial bond strength of the hybrid laminates was determined by ASTM D 3165 lap shear tests. A 3D finite element thermal model was formulated to elucidate the thermal behaviour for increasing first-ply Placement rate. A method for increasing model efficiency was shown to significantly decrease the computational difficulty while maintaining solution accuracy. Raising the first-ply Placement rate from 25 mm/s to 100 mm/s resulted in a fourfold increase in lap shear strength with a maximum value of 22 MPa. The greater strength at higher speeds is attributed to improved synchronisation of the temperature and consolidation pressure history.
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A laser tape Placement Process for selective reinforcement of steel with CF/PA6 composites: Effects of surface preparation and laser angle
Materials and Design, 2017Co-Authors: S. Ehard, Andreas Kollmannsberger, Klaus Drechsler, Paul CompstonAbstract:This paper investigates the manufacture of selectively reinforced hybrid metal/composite laminates in a laser tape Placement Process. Unidirectionally reinforced carbon fibre/PA 6 composite tapes were applied to 2.0mm mild steel substrates. The effects of applying various surface treatments to the steel substrates were investigated including grit blasting and/or the addition of 60μm and 100μm PA 6 film coatings. The effect of the laser angle was also studied. The substrate surface was characterised by profilometry, SEM and optical absorptance. The interfacial bond strength of the hybrid laminates was determined by ASTM D 5868 lap shear tests. Placement onto PA 6 coated substrates was successful with lap shear strengths as high as 30.7MPa achieved for grit blasted substrates coated with a 100μm PA 6 film. The Process was found to have a low sensitivity to laser bias angle.
Andreas Kollmannsberger - One of the best experts on this subject based on the ideXlab platform.
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Steel-CF/PA 6 hybrids manufactured by a laser tape Placement Process: Effect of first-ply Placement rate on lap shear strength for garnet blasted substrates
Procedia Manufacturing, 2019Co-Authors: Christopher Stokes-griffin, Andreas Kollmannsberger, Paul Compston, Klaus DrechslerAbstract:Abstract This paper investigates the manufacture of selectively reinforced metal/composite hybrids in a laser-assisted automated tape Placement Process. Unidirectional carbon fibre/PA 6 composite tapes were applied to 1.9 mm hot rolled steel substrates. The bonding of the first ply to the substrate is critical to the success of the metal-composite hybrid. This work investigates the effect of increasing the first-ply Placement rate for speeds of 25 mm/s, 50 mm/s and 100 mm/s. The steel substrates were pre-treated by garnet blasting and then coating with a 60 μm layer of PA 6. The garnet blasted surface texture was quantified using white light interferometry. The thermal history for bonding of the first ply was measured with fine wire thermocouples. The interfacial bond strength of the hybrid laminates was assessed by ASTM D 3165 lap shear tests. The lap shear strength increased to the highest value of 22.4 MPa at 50 mm/s. Analysis of the fracture surfaces and thermal history suggest that the lower strengths at 25 mm/s and 100 mm/s are due to lower adhesion of the PA 6 coating to the metal substrate, most probably due to lower levels of crystallization.
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manufacture of steel cf pa6 hybrids in a laser tape Placement Process effect of first ply Placement rate on thermal history and lap shear strength
Composites Part A-applied Science and Manufacturing, 2018Co-Authors: Christopher Stokesgriffin, Andreas Kollmannsberger, S. Ehard, Paul Compston, Klaus DrechslerAbstract:Abstract This paper investigates the manufacture of selectively reinforced metal/composite hybrids in a laser-assisted automated tape Placement Process. Carbon-fibre/PA6 composite tapes were applied to PA6-coated steel substrates. The bonding of the first-ply to the substrate is critical to the success of the hybrid; the effect of first-ply Placement rate was investigated for speeds of 25 mm/s, 50 mm/s, 100 mm/s. The interfacial bond strength of the hybrid laminates was determined by ASTM D 3165 lap shear tests. A 3D finite element thermal model was formulated to elucidate the thermal behaviour for increasing first-ply Placement rate. A method for increasing model efficiency was shown to significantly decrease the computational difficulty while maintaining solution accuracy. Raising the first-ply Placement rate from 25 mm/s to 100 mm/s resulted in a fourfold increase in lap shear strength with a maximum value of 22 MPa. The greater strength at higher speeds is attributed to improved synchronisation of the temperature and consolidation pressure history.
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Manufacture of steel–CF/PA6 hybrids in a laser tape Placement Process: Effect of first-ply Placement rate on thermal history and lap shear strength
Composites Part A-applied Science and Manufacturing, 2018Co-Authors: Christopher Stokes-griffin, Andreas Kollmannsberger, S. Ehard, Paul Compston, Klaus DrechslerAbstract:Abstract This paper investigates the manufacture of selectively reinforced metal/composite hybrids in a laser-assisted automated tape Placement Process. Carbon-fibre/PA6 composite tapes were applied to PA6-coated steel substrates. The bonding of the first-ply to the substrate is critical to the success of the hybrid; the effect of first-ply Placement rate was investigated for speeds of 25 mm/s, 50 mm/s, 100 mm/s. The interfacial bond strength of the hybrid laminates was determined by ASTM D 3165 lap shear tests. A 3D finite element thermal model was formulated to elucidate the thermal behaviour for increasing first-ply Placement rate. A method for increasing model efficiency was shown to significantly decrease the computational difficulty while maintaining solution accuracy. Raising the first-ply Placement rate from 25 mm/s to 100 mm/s resulted in a fourfold increase in lap shear strength with a maximum value of 22 MPa. The greater strength at higher speeds is attributed to improved synchronisation of the temperature and consolidation pressure history.
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A laser tape Placement Process for selective reinforcement of steel with CF/PA6 composites: Effects of surface preparation and laser angle
Materials and Design, 2017Co-Authors: S. Ehard, Andreas Kollmannsberger, Klaus Drechsler, Paul CompstonAbstract:This paper investigates the manufacture of selectively reinforced hybrid metal/composite laminates in a laser tape Placement Process. Unidirectionally reinforced carbon fibre/PA 6 composite tapes were applied to 2.0mm mild steel substrates. The effects of applying various surface treatments to the steel substrates were investigated including grit blasting and/or the addition of 60μm and 100μm PA 6 film coatings. The effect of the laser angle was also studied. The substrate surface was characterised by profilometry, SEM and optical absorptance. The interfacial bond strength of the hybrid laminates was determined by ASTM D 5868 lap shear tests. Placement onto PA 6 coated substrates was successful with lap shear strengths as high as 30.7MPa achieved for grit blasted substrates coated with a 100μm PA 6 film. The Process was found to have a low sensitivity to laser bias angle.
