0
Research Papers

Deep-Drawing Forming Trials on a Cross-Ply Thermoplastic Lamina for Helmet Preform Manufacture

[+] Author and Article Information
Lisa M. Dangora, Cynthia J. Mitchell

Department of Mechanical Engineering,
University of Massachusetts Lowell,
1 University Avenue,
Lowell, MA 01854

James Sherwood

Department of Mechanical Engineering,
University of Massachusetts Lowell,
1 University Avenue,
Lowell, MA 01854
e-mail: james_sherwood@uml.edu

Jason C. Parker

US Army Natick Soldier Research,
Development & Engineering Center,
15 Kansas Street,
Natick, MA 01760

1Corresponding author.

Manuscript received December 15, 2015; final manuscript received August 21, 2016; published online October 6, 2016. Assoc. Editor: Yannis Korkolis.This work is in part a work of the U.S. Government. ASME disclaims all interest in the U.S. Government's contributions.

J. Manuf. Sci. Eng 139(3), 031009 (Oct 06, 2016) (8 pages) Paper No: MANU-15-1668; doi: 10.1115/1.4034791 History: Received December 15, 2015; Revised August 21, 2016

With the evolution of modern warfare, there is a constant demand for enhanced soldier protection. The research efforts presented in this paper focus on improving the ballistic performance of composite combat helmets through the control of fiber orientations, reduction of seam density, and preservation of long fiber lengths. To accomplish these objectives, near-net-shape preforming is explored as an alternative method to the traditional cut and dart techniques used in the manufacture of combat helmets. An overview of current fabrication procedures is provided in addition to a discussion of the material selection and preform processing technique. Forming trials are conducted on Dyneema® HB80, a cross-ply thermoplastic lamina, using a laboratory deep-draw setup to explore the effects of processing parameters on the quality of the formed part. Undesirable wrinkling that manifests during deep-drawing of the material is found to be most effectively mitigated through the use of sufficient binder pressure. Furthermore, it is demonstrated that a loose ply stack up is more amenable to the production of high-quality preforms than a preconsolidated charge of material.

FIGURES IN THIS ARTICLE
<>
Copyright © 2017 by ASME
Your Session has timed out. Please sign back in to continue.

References

Cunniff, P. M. , and Parker, J. , 2008, “ The Effect of Preform Shape on Ballistic Impact Performance, Coverage and Seam Density in Combat Helmets,” 24th International Symposium on Ballistics, New Orlean, LA, pp. 618–625.
Campbell, D. T. , and Cramer, D. R. , 2008, “ Hybrid Thermoplastic Composite Ballistic Helmet Fabrication Study,” Sampe '08: Polymer Library.
Alesi, A. L. , Richard, P. A. , Roger, A. G. , Alan, M. L. , and Joseph, J. P. , 1975, “ New Materials and Construction for Improved Helmets,” Army Materials and Mechanics Research Center, Watertown, MA, Paper No. AMMRC-MS-75-9.
Folgar, F. , Brian, R. S. , Shawn, M. W. , and James, W. , 2007, “ Thermoplastic Matrix Combat Helmet With Graphite-Epoxy Skin,” 23rd International Symposium on Ballistics, Tarragona, Spain, Apr. 16–20, pp. 883–892.
Hoa, S. V. , 2009, Principles of the Manufacturing of Composite Materials, DEStech Publications, Lancaster, PA.
Strong, A. B. , 2008, Fundamentals of Composites Manufacturing: Materials, Methods and Applications, Society of Manufacturing Engineers, Dearborn, MI.
Bloom, L. D. , Wang, J. , and Potter, K. D. , 2013, “ Damage Progression and Defect Sensitivity: An Experimental Study of Representative Wrinkles in Tension,” Composites Part B, 45(1), pp. 449–458. [CrossRef]
Potter, K. , Khan, B. , Wisnom, M. , Bell, T. , and Stevens, J. , 2008, “ Variability, Fibre Waviness and Misalignment in the Determination of the Properties of Composite Materials and Structures,” Composites Part A, 39(9), pp. 1343–1354. [CrossRef]
Potter, K. D. , 2009, “ Understanding the Origins of Defects and Variability in Composites Manufacture,” International Conference on Composite Materials (ICCM)-17, Edinburgh, UK.
McConnell, V. P. , 2009, “ Antiballistics: Composites in the Cross Hairs,” Composites Technology, CompositesWorld, Nov. 17, epub.
National Research Council, 1997, Tactical Display for Soldiers: Human Factors Considerations, Physical Ergonomics of Infantry Helmet, National Academies Press, Washington, DC.
Faur-Csukat, G. , 2006, “ A Study on the Ballistic Performance of Composites,” Macromol. Symp., 239(1), pp. 217–226. [CrossRef]
McConnell, V. P. , 2006, “ Ballistic Protection Materials a Moving Target,” Reinf. Plast., 50(11), pp. 20–25. [CrossRef]
National Research Council, 2014, Review of Department of Defense Test Protocols for Combat Helmets, National Academies Press, Washington, DC.
Bhattacharyya, D. , and Åström, T. , 1997, Composite Sheet Forming, Vol. 11, Elsevier, Amsterdam, The Netherlands.
Song, J. W. , 2003, “ Thermoplastic Composites for Ballistic Application,” Doctoral dissertation, University of Massachusetts Lowell, Lowell, MA.
Kulkarni, S. G. , Gao, X.-L. , Horner, S. E. , Zheng, J. Q. , and David, N. V. , 2013, “ Ballistic Helmets–Their Design, Materials, and Performance Against Traumatic Brain Injury,” Compos. Struct., 101, pp. 313–331. [CrossRef]
DSM Dyneema, 2014, “ Anti-Ballistic Protection for Personal and Military Vehicle Protection,” Dyneema, Heerlen, The Netherlands.
Roylance, D. , and Wang, S.-S. , 1878, “ Penetration Mechanics of Textile Structures: Influence of Non–Linear Viscoelastic Relaxation,” Polymer Eng. Sci., 18(14), pp. 1068–1072.
Hyer, M. W. , 2009, Stress Analysis of Fiber-Reinforced Composite Materials, DEStech Publications, Lancaster, PA.
Cunniff, P. M. , 1992, “ An Analysis of the System Effects in Woven Fabrics Under Ballistic Impact,” Text. Res. J., 62(9) pp. 495–509. [CrossRef]
Åström, T. , 1997, Thermoplastic Composite Sheet Forming: Materials and Manufacturing Techniques, Elsevier, Amsterdam, The Netherlands.
Cherouat, A. , and Billoët, J. L. , 2001, “ Mechanical and Numerical Modelling of Composite Manufacturing Processes Deep-Drawing and Laying-Up of Thin Pre-Impregnated Woven Fabrics,” J. Mater. Processing Technol., 118(1), pp. 460–471. [CrossRef]
Jauffrès, D. , Sherwood, J. A. , Morris, C. D. , and Chen, J. , 2010, “ Discrete Mesoscopic Modeling for the Simulation of Woven-Fabric Reinforcement Forming,” Int. J. Mater. Form., 3(2), pp. 1205–1216. [CrossRef]
Dangora, L. M. , Cynthia, J. M. , and Sherwood, J. A. , 2015, “ Predictive Model for the Detection of Out-of-Plane Defects Formed During Textile-Composite Manufacture,” Composites Part A, 78, pp. 102–112. [CrossRef]
Sekine, N. , Takao, T. , Shoji, T. , Toyama, H. , Kashiwazaki, K. , Sugasawa, N. , Nakamura, K. , Kashima, T. , Yamanaka, A. , Takeo, M. , and Sato, S. , 2001, “ Frictional Coefficients of Structural Materials in AC Superconducting Coils,” Cryogenics 41(5), pp. 379–384. [CrossRef]
Dangora, L. M. , Christopher, J. H. , Cynthia, J. M. , James, A. S. , and Jason, C. P. , 2015, “ Challenges Associated With Shear Characterization of a Cross-Ply Thermoplastic Lamina Using Picture Frame Tests,” Composites Part A, 78, pp. 181–190. [CrossRef]
Breuer, U. , Neitzel, M. , Ketzer, V. , and Reinicke, R. , 1996, “ Deep-Drawing of Fabric‐Reinforced Thermoplastics: Wrinkle Formation and Their Reduction,” Polym. Compos., 17(4), pp. 643–647. [CrossRef]

Figures

Grahic Jump Location
Fig. 1

Generic darted pinwheel pattern cut into sheet goods to facilitate helmet forming. Plies align with overlaying crowns and staggered petals for full helmet coverage and even seam distribution.

Grahic Jump Location
Fig. 2

Generic deep-draw process for forming a heated ply stack to the punch geometry as it is drawn into an open mold

Grahic Jump Location
Fig. 3

(a) Laboratory preform setup consisting of a hemispherical male tool, an open female die, and a binder ring (shown here within an environmental chamber mounted on a universal testing machine) and (b) corresponding computational tooling with prescribed loading conditions and constraints

Grahic Jump Location
Fig. 4

Degree of shear necessary for cross-ply to conform to hemispherical punch at a 1:1 draw ratio. Note: The results were generated using modeling technique described in Ref. [24] with a 3 mm element length.

Grahic Jump Location
Fig. 5

A conservation of volume approximation is used to calculate the change in lamina thickness as a function of shear, which correlates well with experimental data

Grahic Jump Location
Fig. 6

(a) FEA contour of thickness change from the nominal sheet value of 0.148 mm plotted on the undeformed lamina and (b) potential filler-ply pattern with cutouts to promote uniform preform thickness

Grahic Jump Location
Fig. 7

Forming example where buckling forces exceed the pressure applied by the binder, causing the draw ring to lift and resulting in severe wrinkling

Grahic Jump Location
Fig. 8

Deep-draw force profile at various temperatures for tests with a punch velocity of 6.35 mm/s and a binder pressure of 700 Pa

Grahic Jump Location
Fig. 9

Severe wrinkling of hemisphere formed at 100 °C with 2900 Pa of binder pressure (6.35 mm/s)

Grahic Jump Location
Fig. 10

Wrinkling moderated with increased binder pressure of 4000 Pa at 100 °C (6.35 mm/s)

Grahic Jump Location
Fig. 11

Deep-draw force profile at various binder pressures for tests with a punch velocity of 6.35 mm/s and a forming temperature of 100 °C

Grahic Jump Location
Fig. 12

Preconsolidated layup (a) before and (b) after deep-drawing (100 °C, 6.35 mm/s, 6.5 kPa)

Grahic Jump Location
Fig. 13

Unconsolidated layup drawn to hemisphere geometry (100 °C, 6.35 mm/s, 6.5 kPa). Note that the smallest ply detached upon removal from the tooling and is shown here to the side.

Grahic Jump Location
Fig. 14

Unconsolidated layup drawn to hemisphere geometry with filler ply secured in a sandwich between two full plies

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In