Improving impact performance in D-‐LFT composites via...
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Improving impact performance in DLFT composites via UDtape based fabrics & tailored laminates A study was conducted on inline compounded directlongfiber thermoplasAc (DLFT) composites to evaluate methods to increase energy absorpAon of glassreinforced polypropylene in an impact scenario through addiAon of unidirecAonalglass (UD) tapebased fabrics and tailored laminates. Results indicate such hybrid structures may open new opportuniAes for thermoplasAc composites produced in the tailored DLFT process for a variety of market segments. The study demonstrated the benefit of a hybrid molding process like tailored DLFT that allows a number of parameters (e.g. cost, weight, moldability, and higher mechanicals where needed) to be balanced and hence it can provide manufacturers with the best cost/performance raAo for a given applicaAon. Improving Impact ProperAes of DLFT Composites Recognizing the benefits of tailored DLFT for any industry desiring to improve the mechanical performance of thermoplas>c composites, 4 companies funded a study to 1) evaluate the effects on impact proper>es of using UDglass tapebased products (which subsequently were fabricated into intermediate fabrics and tailored laminates) in the tailored DLFT process; and 2) check that tailored DLFT is a viable process for demanding produc>onmolding opera>ons of complex parts. Ticona Engineering Polymers supplied PPimpregnated UDglassreinforced tapes that Oxeon AB, with exper>se in producing spread tow reinforcements (based on tapes instead of yarns), used to produce fabric weaves. Fiberforge also used the tapes to produce Tailored Blank tape laminates using its patented process for conver>ng preimpregnated thermoplas>c tapes. In turn, Fraunhofer Ins>tute for Chemical Technology – a fully equipped R&D center with significant exper>se in the field of polymer composites – compounded PPbased DLFT material and used various combina>ons of the DLFT charge, tape fabrics, and tailored laminates in different layup configura>ons and thicknesses to compression mold test plaques and later an actual automo>ve part. Study Overview A 2part study was conducted. First, different combina>ons of pure DLFT, pure tape fabrics, and pure tailored laminates in various thicknesses, plus a number of hybrid combina>ons were laid up in a simple, flat plaque tool (400 x 400 mm) and compression molded. Twenty material and layup combina>ons were successfully produced and the most representa>ve are shown in Table I (pure DLFT, pure tape laminate, pure tape fabric and a number of hybrid configura>ons). One plaque was produced for each combina>on, and then 6 standard test coupons were removed from each plaque. For hybrid configura>ons, 2 plaques were produced to allow researchers to cut sufficient coupons to impact samples on both the DLFT side as well as the UD tape fabric/laminate side. A minimum of 5 samples from each plaque were subjected to EN ISO 66032 (with the remaining sample kept as a control). This process allowed for a rapid evalua>on of a number of different layup and material combina>ons, and permi`ed researchers to quickly determine which samples represented the best performing arrangements. The purpose of the second part of the study was to determine if goodquality tailored DLFT parts could be made quickly enough to be prac>cal in a commercial produc>on environment using the UDglass products. With knowledge gained from the flat plaque tests, researchers developed a new layup pa`ern with all 3 materials and molded this in a larger (1,113 x 775 mm) tool loaned by Minda Schenk Plas>c Solu>ons. This tool was an automo>ve series produc>on mold used to produce engine noise shields that are mounted under the front end of a European passenger car. The shield was a challenging design with segments of tall, thin ribs that would be hard to fill with UDglass products alone. Since this was a commercial tool meant for con>nuous part produc>on, it had no hea>ng/cooling lines so was kept at molding temperatures between rounds of molding the hybrid layups by molding conven>onal DLFT parts. Materials Selec2on Ticona supplied 0.25mm thick PP/glass UD tapes (Celstran CFRTP PPGF70 with 70 wt% glass) in a variety of widths depending on how they would be used. Oxeon converted these into tape fabrics (TeXtreme plain weaves that were 0.50mm thick per ply and were laid up 2 plies thick in either a 0°/90° = (0/90) or a ± 45° configura>on = (± 45). In turn, the double plies were used to build stacked configura>ons in specific thicknesses that were not preconsolidated. Fiberforge also used the tapes to produce tailored laminates (consolidated Tailored Blanks). For Part 1 (the plaque study), the laminates were supplied in single sheets (to be cut to size as needed) and several and configura>ons, e.g.0°/90° = (0/90) with a thickness of 0.5, 1.0, or 2.0 mm; or a quasi isotropic (0°/90°/+45°/45°) s where “s” represents a symmetric layup of 8 plies. For Part 2 (the engineshield study), Fiberforge produced both partshape tailored laminates and large sheets of laminate, which were then cut to size and shape as needed. In both cases, the tape laminates were preconsolidated. The tape fabrics and tailored laminates were used alone or paired with inline compounded DLFT composite produced by Fraunhofer with an ILC unit supplied by Dieffenbacher GmbH using PP resin (PPC71170 RNA from Dow Chemical), an addi>ves package (Priex 20078 coupling agent and AddVance 453 stabilizer from Addcomp Holland BV); and discon>nuous choppedglass fiber (JM 490 2400 tex glass by Johns Manville). The glass loading level of the DLFT formula>on differed between the ini>al plaque study (which featured 30 wt% glass, the mostcommon automo>ve loading level) and the larger automo>ve part (which featured 20 wt% glass to enhance fill in the part’s far more complex geometry). www.JECcomposites.com Michael Ruby* & Daniel Grauer, Ticona Engineering Polymers Benjamin Hangs & Frank Henning, Fraunhofer Ins>tute for Chemical Technology Andreas Martsman, Oxeon AB Simon T. Jespersen, Fiberforge (not shown) * michael.ruby@>cona.com a`empted and 20 were successfully produced. Table I above provides details on 11 of the most interes>ng and representa>ve configura>ons (including pure DLFT, pure tape fabrics, pure tailored laminates, and a variety of hybrid layups in different thicknesses and orienta>ons) from this part of the study. Use of Precolored Material to Evaluate Material Movement in Shield Molding Trials In Part 2 of the study with the engine shield tool, researchers wanted to understand how the materials moved/flowed during molding, so they precolored each type to enhance visibility. Ticona’s UD tapes were supplied in black (for use in the fabric weaves Oxeon would produce), and yellow (for the Tailored Blank laminates Fiberforge would produce). Ticona also supplied a blue color masterbatch for the D LFT material to be compounded by Fraunhofer. Figure 1 below shows how the precolored black tape fabric, yellow tailored laminate, and blue DLFT charge looked prior to molding in Part 2’s engineshield tool. Figure 2 shows the part (front and back/roadfacing side and vehiclefacing side) auer molding. The DLFT charge was used primarily to mold the vehiclefacing (back) side of the part as the most complex ribbing was located there; the tailored laminate and tape fabric were used on the front (roadfacing) side of the part as that loca>on sees the most damaging condi>ons and the UD glass in both fabrics and tailored laminates would have had challenges penetra>ng the tall thin ribs on the reverse side of the part. Prehea2ng / Molding Parameters To ensure good fusion between recently compounded DLFT charge (exi>ng the ILC unit at close to 200C) and previously produced tape fabric and/or tailored laminate, it was necessary to preheat the la`er prior to molding using an infrared (IR) oven at PP’s processing temperature (near 200C). Hea>ng >me for both fabrics and tailored laminates varied depending on thickness of material and with unconsolidated / consolidated forms of the semifinished products. Both the flat plaque tool and the more complex engine shield tool were molded on a 36,000kN compression press. The smaller, flat plaques were molded at ≈3,200 kN pressure for 45 sec at 75C; the more complex shields were molded at ≈12,000 kN pressure for 30 sec in a much cooler tool of ≈4045C. The difference in dwell >me and temperature was a func>on of thickness. The ILC unit, IR oven, and compression press were in close proximity, so tape fabrics and/or tailored laminates could heat while DLFT was compounded and parts were molded. For the shield part, this yielded an effec>ve cycle >me of ≈70 sec to produce a part, although actual dwell >me in the tool was 30 sec and researchers note that this was under unop>mized condi>ons. Results, ObservaAons & SuggesAons Flat Plaque Tes2ng – Were Impact Results Improved? Previous research suggested that the UDtape products would significantly increase not only s>ffness/strength but also impact proper>es, and impact results confirmed this. Figure 3 below shows results of some representa>ve samples. The pure tape fabrics and pure tape laminates yielded energy at maximum force (blue bars) and total energy (red bars) values that were approximately 9x higher than those measured from the baseline/control pure DLFT material regardless of thickness. This shows the benefit of greater retained fiber length and higher FVFs on improving mechanical proper>es in composites. (It should be noted that while Figure 3 is useful for no>ng qualita>ve trends, it cannot be used to pull quan>ta>ve values from samples measured at different thicknesses, since both Young’s modulus and the second moment of iner>a (and therefore coupon bending during impact) are strongly influenced by nominal wall thickness.) Interes>ng results were also seen on hybrid samples containing tape fabric and/or tailored laminate plus DLFT. As previously noted, hybrid samples were tested by impac>ng the DLFT side as well as the tape fabric and/or tailored laminate side from each hybrid test plaque, representa>ve results of which are shown in Figure 4. As with Figure 3, the red bars represent total energy absorbed and the blue bars represent maximum force. For each set of samples (DLFT side vs. tape fabric and/or tailored laminate side), trends indicate that energy at maximum force is always lower on the DLFT side of the sample than on the tape fabric and/or tailored laminate side, while the reverse is true for total energy absorbed. Researchers theorize that because the DLFT side with shorter, discon>nuous glass at lower FVF loadings is not as s>ff / strong as the side with UDtape fabrics and/or tailored laminates, which also have higher FVFs as well as longer glass, that it breaks earlier and more easily in the impact test (e.g. lower energy at maximum force). The reverse is true for the s>ffer/stronger tape fabric and/or tailored laminate side, which requires more energy to break (higher energy at maximum force). As the DLFT side breaks, it puts the UDglass into tension, so when that impactor breaks through the DLFT side and hits the UDglass side, there is less kine>c energy leu to break the UDglass in the sample (higher total energy absorbed). All impacted samples broke in the test. Engine Shield Produc2on – Was Process Fast Enough for Commercial Produc2on? Since compounding, hea>ng, and molding cells were located in close proximity, mul>ple steps could be completed simultaneously, giving an effec>ve molding cycle for the engine shield of 70 sec, which makes the process compa>ble for mediumto high produc>on volumes. Typical cycle >mes in commercial thermoplas>c compression molding opera>ons range from 30 sec for thinner, smaller parts to 90 sec for larger and thicker parts, so a 70 sec cycle >me is within the target range. However, it should be noted that this was a nonop>mized process and that it was the prehea>ng opera>on that was the limi>ng step in the process sequence, not the actual molding >me of 30 sec or the ILC unit, which is capable of producing DLFT compound at a rate of 8 kg/min. Researchers feel that with further work (e.g. staged oven, automated handling equipment, use of preconsolidated fabrics or laminates, and a tool equipped with clamps/fixtures), that it should be possible to drop the effec>ve cycle >me significantly lower than 70 sec, which would make the tailored D LFT faster and even more costeffec>ve vs. alterna>ve materials/process combina>ons. Figure 1 (le3) shows precolored fabric, laminate, and DLFT charge prior to molding; Figure 2 (right) shows front (top, roadfacing) and back (bo@om, vehiclefacing) sides of the part a3er molding. Figure 3: Energy at maximum force and total energy for pure DLFT (at 2.0, 2.5, & 3.0 mm thickness) vs. pure tape laminates and pure tape fabrics (both at 2.0mm thickness) showing a 9x improvement in performance with use of UDglass reinforcements Figure 4: Energy at maximum force (blue bars) and total energy (red bars) for select hybrid samples impacted on both DLFT and tape fabric and/or tailored laminate sides of the hybrid configuraRons Hybrid Layup CombinaAons Materials Used Nominal Wall (mm) No. of Plies/ Layers Fiber OrientaAon of Each Ply ( o ) V1 Pure Tape Fabric 2.0 4 (0/90) V2 Pure Tape Laminate 2.0 1 (0/90)2 s V3 Pure DLFT 2.0 Not applicable DLFT V4 Pure DLFT 2.5 Not applicable DLFT V5 Pure DLFT 3.0 Not applicable DLFT V6 Hybrid of Tape Fabric + DLFT 0.5 + 2.5 1 (0/90) + DLFT V7 Hybrid of Tape Laminate + DLFT 0.5 + 2.5 1 (0/90) + DLFT V8 Hybrid of Tape Fabric + DLFT 1.0 + 2.0 2 2 x (0/90) + DLFT V9 Hybrid of Tape Laminate+ DLFT 1.0 + 2.0 1 (0/90)s + DLFT V10 Hybrid of Tape Fabric + Tape Laminate + DLFT 2 x 0.5 + 2.0 1+1 (0/90) + (0/90) + DLFT V11 Hybrid of Tape Laminate + Tape Fabric + DLFT 2 x 0.5 + 2.0 1+1 (0/90) + (0/90) + DLFT Table I: Select materials/layup/orientaRon/thicknesses for Part 1 flat test plaques Layup Configura2ons Produced in Plaque Molding Trials For the Phase 1 plaque study, 21 material/layup combina>ons were
Transcript of Improving impact performance in D-‐LFT composites via...
Improving impact performance in D-‐LFT composites via UD-‐tape based fabrics & tailored laminates
A study was conducted on inline compounded direct-‐long-‐fiber thermoplasAc (D-‐LFT) composites to evaluate methods to increase energy absorpAon of glass-‐reinforced polypropylene in an impact scenario through addiAon of unidirecAonal-‐glass (UD) tape-‐based fabrics and tailored laminates. Results indicate such hybrid structures may open new opportuniAes for thermoplasAc composites produced in the tailored D-‐LFT process for a variety of market segments.
The study demonstrated the benefit of a hybrid molding process like tailored D-‐LFT that allows a number of parameters (e.g. cost, weight, moldability, and higher mechanicals where needed) to be balanced and hence it can provide manufacturers with the best cost/performance raAo for a given applicaAon.
Improving Impact ProperAes of D-‐LFT Composites Recognizing the benefits of tailored D-‐LFT for any industry desiring to improve the mechanical performance of thermoplas>c composites, 4 companies funded a study to 1) evaluate the effects on impact proper>es of using UD-‐glass tape-‐based products (which subsequently were fabricated into intermediate fabrics and tailored laminates) in the tailored D-‐LFT process; and 2) check that tailored D-‐LFT is a viable process for demanding produc>on-‐molding opera>ons of complex parts. Ticona Engineering Polymers supplied PP-‐impregnated UD-‐glass-‐reinforced tapes that Oxeon AB, with exper>se in producing spread tow reinforcements (based on tapes instead of yarns), used to produce fabric weaves. Fiberforge also used the tapes to produce Tailored Blank tape laminates using its patented process for conver>ng preimpregnated thermoplas>c tapes. In turn, Fraunhofer Ins>tute for Chemical Technology – a fully equipped R&D center with significant exper>se in the field of polymer composites – compounded PP-‐based D-‐LFT material and used various combina>ons of the D-‐LFT charge, tape fabrics, and tailored laminates in different layup configura>ons and thicknesses to compression mold test plaques and later an actual automo>ve part. Study Overview A 2-‐part study was conducted. First, different combina>ons of pure D-‐LFT, pure tape fabrics, and pure tailored laminates in various thicknesses, plus a number of hybrid combina>ons were laid up in a simple, flat plaque tool (400 x 400 mm) and compression molded. Twenty material and layup combina>ons were successfully produced and the most representa>ve are shown in Table I (pure D-‐LFT, pure tape laminate, pure tape fabric and a number of hybrid configura>ons). One plaque was produced for each combina>on, and then 6 standard test coupons were removed from each plaque. For hybrid configura>ons, 2 plaques were produced to allow researchers to cut sufficient coupons to impact samples on both the D-‐LFT side as well as the UD-‐tape fabric/laminate side. A minimum of 5 samples from each plaque were subjected to EN ISO 6603-‐2 (with the remaining sample kept as a control). This process allowed for a rapid evalua>on of a number of different layup and material combina>ons, and permi`ed researchers to quickly determine which samples represented the best-‐performing arrangements. The purpose of the second part of the study was to determine if good-‐quality tailored D-‐LFT parts could be made quickly enough to be prac>cal in a commercial produc>on environment using the UD-‐glass products. With knowledge gained from the flat-‐plaque tests, researchers developed a new layup pa`ern with all 3 materials and molded this in a larger (1,113 x 775 mm) tool loaned by Minda Schenk Plas>c Solu>ons. This tool was an automo>ve series produc>on mold used to produce engine noise shields that are mounted under the front end of a European passenger car. The shield was a challenging design with segments of tall, thin ribs that would be hard to fill with UD-‐glass products alone. Since this was a commercial tool meant for con>nuous part produc>on, it had no hea>ng/cooling lines so was kept at molding temperatures between rounds of molding the hybrid layups by molding conven>onal D-‐LFT parts. Materials Selec2on Ticona supplied 0.25-‐mm thick PP/glass UD tapes (Celstran CFR-‐TP PP-‐GF70 with 70 wt-‐% glass) in a variety of widths depending on how they would be used. Oxeon converted these into tape fabrics (TeXtreme plain weaves that were 0.50-‐mm thick per ply and were laid up 2 plies thick in either a 0°/90° = (0/90) or a ± 45° configura>on = (± 45). In turn, the double plies were used to build stacked configura>ons in specific thicknesses that were not preconsolidated. Fiberforge also used the tapes to produce tailored laminates (consolidated Tailored Blanks). For Part 1 (the plaque study), the laminates were supplied in single sheets (to be cut to size as needed) and several and configura>ons, e.g.0°/90° = (0/90) with a thickness of 0.5, 1.0, or 2.0 mm; or a quasi-‐isotropic (0°/90°/+45°/-‐45°)s where “s” represents a symmetric layup of 8 plies. For Part 2 (the engine-‐shield study), Fiberforge produced both part-‐shape tailored laminates and large sheets of laminate, which were then cut to size and shape as needed. In both cases, the tape laminates were preconsolidated. The tape fabrics and tailored laminates were used alone or paired with inline compounded D-‐LFT composite produced by Fraunhofer with an ILC unit supplied by Dieffenbacher GmbH using PP resin (PP-‐C711-‐70 RNA from Dow Chemical), an addi>ves package (Priex 20078 coupling agent and AddVance 453 stabilizer from Addcomp Holland BV); and discon>nuous chopped-‐glass fiber (JM 490 2400 tex glass by Johns Manville). The glass loading level of the D-‐LFT formula>on differed between the ini>al plaque study (which featured 30 wt-‐% glass, the most-‐common automo>ve loading level) and the larger automo>ve part (which featured 20 wt-‐% glass to enhance fill in the part’s far more complex geometry).
www.JECcomposites.com
Michael Ruby* & Daniel Grauer, Ticona Engineering Polymers Benjamin Hangs & Frank Henning, Fraunhofer Ins>tute for Chemical Technology Andreas Martsman, Oxeon AB Simon T. Jespersen, Fiberforge (not shown)
* michael.ruby@>cona.com
a`empted and 20 were successfully produced. Table I above provides details on 11 of the most interes>ng and representa>ve configura>ons (including pure D-‐LFT, pure tape fabrics, pure tailored laminates, and a variety of hybrid layups in different thicknesses and orienta>ons) from this part of the study. Use of Precolored Material to Evaluate Material Movement in Shield Molding Trials In Part 2 of the study with the engine shield tool, researchers wanted to understand how the materials moved/flowed during molding, so they precolored each type to enhance visibility. Ticona’s UD tapes were supplied in black (for use in the fabric weaves Oxeon would produce), and yellow (for the Tailored Blank laminates Fiberforge would produce). Ticona also supplied a blue color masterbatch for the D-‐LFT material to be compounded by Fraunhofer. Figure 1 below shows how the precolored black tape fabric, yellow tailored laminate, and blue D-‐LFT charge looked prior to molding in Part 2’s engine-‐shield tool. Figure 2 shows the part (front and back/road-‐facing side and vehicle-‐facing side) auer molding. The D-‐LFT charge was used primarily to mold the vehicle-‐facing (back) side of the part as the most complex ribbing was located there; the tailored laminate and tape fabric were used on the front (road-‐facing) side of the part as that loca>on sees the most damaging condi>ons and the UD glass in both fabrics and tailored laminates would have had challenges penetra>ng the tall thin ribs on the reverse side of the part. Prehea2ng / Molding Parameters To ensure good fusion between recently compounded D-‐LFT charge (exi>ng the ILC unit at close to 200C) and previously produced tape fabric and/or tailored laminate, it was necessary to preheat the la`er prior to molding using an infrared (IR) oven at PP’s processing temperature (near 200C). Hea>ng >me for both fabrics and tailored laminates varied depending on thickness of material and with unconsolidated / consolidated forms of the semi-‐finished products. Both the flat plaque tool and the more complex engine shield tool were molded on a 36,000-‐kN compression press. The smaller, flat plaques were molded at ≈3,200 kN pressure for 45 sec at 75C; the more complex shields were molded at ≈12,000 kN pressure for 30 sec in a much cooler tool of ≈40-‐45C. The difference in dwell >me and temperature was a func>on of thickness. The ILC unit, IR oven, and compression press were in close proximity, so tape fabrics and/or tailored laminates could heat while D-‐LFT was compounded and parts were molded. For the shield part, this yielded an effec>ve cycle >me of ≈70 sec to produce a part, although actual dwell >me in the tool was 30 sec and researchers note that this was under unop>mized condi>ons.
Results, ObservaAons & SuggesAons Flat Plaque Tes2ng – Were Impact Results Improved? Previous research suggested that the UD-‐tape products would significantly increase not only s>ffness/strength but also impact proper>es, and impact results confirmed this. Figure 3 below shows results of some representa>ve samples. The pure tape fabrics and pure tape laminates yielded energy at maximum force (blue bars) and total energy (red bars) values that were approximately 9x higher than those measured from the baseline/control pure D-‐LFT material regardless of thickness. This shows the benefit of greater retained fiber length and higher FVFs on improving mechanical proper>es in composites. (It should be noted that while Figure 3 is useful for no>ng qualita>ve trends, it cannot be used to pull quan>ta>ve values from samples measured at different thicknesses, since both Young’s modulus and the second moment of iner>a (and therefore coupon bending during impact) are strongly influenced by nominal wall thickness.) Interes>ng results were also seen on hybrid samples containing tape fabric and/or tailored laminate plus D-‐LFT. As previously noted, hybrid samples were tested by impac>ng the D-‐LFT side as well as the tape fabric and/or tailored laminate side from each hybrid test plaque, representa>ve results of which are shown in Figure 4. As with Figure 3, the red bars represent total energy absorbed and the blue bars represent maximum force. For each set of samples (D-‐LFT side vs. tape fabric and/or tailored laminate side), trends indicate that energy at maximum force is always lower on the D-‐LFT side of the sample than on the tape fabric and/or tailored laminate side, while the reverse is true for total energy absorbed. Researchers theorize that because the D-‐LFT side with shorter, discon>nuous glass at lower FVF loadings is not as s>ff / strong as the side with UD-‐tape fabrics and/or tailored laminates, which also have higher FVFs as well as longer glass, that it breaks earlier and more easily in the impact test (e.g. lower energy at maximum force). The reverse is true for the s>ffer/stronger tape fabric and/or tailored laminate side, which requires more energy to break (higher energy at maximum force). As the D-‐LFT side breaks, it puts the UD-‐glass into tension, so when that impactor breaks through the D-‐LFT side and hits the UD-‐glass side, there is less kine>c energy leu to break the UD-‐glass in the sample (higher total energy absorbed). All impacted samples broke in the test. Engine Shield Produc2on – Was Process Fast Enough for Commercial Produc2on? Since compounding, hea>ng, and molding cells were located in close proximity, mul>ple steps could be completed simultaneously, giving an effec>ve molding cycle for the engine shield of 70 sec, which makes the process compa>ble for medium-‐to-‐high produc>on volumes. Typical cycle >mes in commercial thermoplas>c compression molding opera>ons range from 30 sec for thinner, smaller parts to 90 sec for larger and thicker parts, so a 70 sec cycle >me is within the target range. However, it should be noted that this was a non-‐op>mized process and that it was the prehea>ng opera>on that was the limi>ng step in the process sequence, not the actual molding >me of 30 sec or the ILC unit, which is capable of producing D-‐LFT compound at a rate of 8 kg/min. Researchers feel that with further work (e.g. staged oven, automated handling equipment, use of preconsolidated fabrics or laminates, and a tool equipped with clamps/fixtures), that it should be possible to drop the effec>ve cycle >me significantly lower than 70 sec, which would make the tailored D-‐LFT faster and even more cost-‐effec>ve vs. alterna>ve materials/process combina>ons.
Figure 1 (le3) shows precolored fabric, laminate, and D-‐LFT charge prior to molding; Figure 2 (right) shows front (top, road-‐facing) and back (bo@om, vehicle-‐facing) sides of the part a3er molding.
Figure 3: Energy at maximum force and total energy for pure D-‐LFT (at 2.0-‐, 2.5-‐, & 3.0-‐mm thickness) vs. pure tape laminates and pure tape fabrics (both at 2.0-‐mm thickness) showing a 9x improvement in performance with use of UD-‐glass reinforcements
Figure 4: Energy at maximum force (blue bars) and total energy (red bars) for select hybrid samples impacted on both D-‐LFT and tape fabric and/or tailored laminate sides of the hybrid configuraRons
Hybrid Layup CombinaAons
Materials Used Nominal Wall (mm)
No. of Plies/Layers
Fiber OrientaAon of Each Ply (o)
V1 Pure Tape Fabric 2.0 4 (0/90)
V2 Pure Tape Laminate 2.0 1 (0/90)2s
V3 Pure D-‐LFT 2.0 Not applicable D-‐LFT
V4 Pure D-‐LFT 2.5 Not applicable D-‐LFT
V5 Pure D-‐LFT 3.0 Not applicable D-‐LFT
V6 Hybrid of Tape Fabric + D-‐LFT 0.5 + 2.5 1 (0/90) + D-‐LFT
V7 Hybrid of Tape Laminate + D-‐LFT 0.5 + 2.5 1 (0/90) + D-‐LFT
V8 Hybrid of Tape Fabric + D-‐LFT 1.0 + 2.0 2 2 x (0/90) + D-‐LFT
V9 Hybrid of Tape Laminate+ D-‐LFT 1.0 + 2.0 1 (0/90)s + D-‐LFT
V10 Hybrid of Tape Fabric + Tape Laminate + D-‐LFT 2 x 0.5 + 2.0 1+1 (0/90) + (0/90) + D-‐LFT
V11 Hybrid of Tape Laminate + Tape Fabric + D-‐LFT 2 x 0.5 + 2.0 1+1 (0/90) + (0/90) + D-‐LFT
Table I: Select materials/layup/orientaRon/thicknesses for Part 1 flat test plaques
Layup Configura2ons Produced in Plaque Molding Trials For the Phase 1 plaque study, 21 material/layup combina>ons were
