Effects of Blade Tip Profile on In-Plane Tensile Properties of Wedge-Notched Polypropylene Sheet
Shigeru Nagasawa*,, Akihiro Yamamoto**, Thepwachara Ruchirabha*, and Kazuki Umemoto*
*Department of Mechanical Engineering, Nagaoka University of Technology
1603-1 Kamitomioka, Nagaoka, Niigata 940-2188, Japan
**FANUC Corporation, Oshino-mura, Japan
In this work, the tensile characteristics of a 0.2-mm-thick polypropylene (PP) sheet subjected to indentation with virgin and blunt knives (apex angle, α=42◦; tip thickness, w=6 and 20 μm, respectively), were experimentally investigated. To determine the effect of mechanical condition, such as the notched depth and the profile of the root surface, on the breaking behavior of the half-cut PP specimen, the tensile testing of the half-cut specimen was carried out by varying the indentation depth and tensile velocity. By the experiments, the breakage behavior of the scored (half-cut) zone was determined by varying the indentation depth, tip thickness of the blade, and elongation rate. A kind of crazing or cracking by the blunt knife decreased the tensile resistance and burr elongation for an indentation depth larger than 0.9, whereas the work hardening by the blunt knife increased these properties for an indentation depth less than 0.8. When a blunt knife was used at a high elongation rate larger than 0.01 s-1, the half-cut zone of the PP sheet exhibited brittle fracture, i.e., the tensile resistance and burr elongation decreased.
-  F. von Hesse and H. J. Tenzer, “Grundlagen der Papier-verarbeitung – Band 2: Arbeitsverfahren der Papierverarbeitung,” VEB Verlag für Buch- und Biblio-Thekswesen, pp. 58-60, 1963 (in Germany).
-  S. Mizuguchi (Eds.), “Advanced Technology on Industrial Packaging and Transportation,” Fuji Techno System, pp. 58-59, 2002 (in Japanese).
-  Y. Inaba, “Innovation in Flatbed Die-Cutting of Folding Carton,” J. of Packaging Science & Technology, Japan, Vol.25 No.5, pp. 225-232, 2016 (in Japanese).
-  R. J. Crawford, “Plastics Engineering 3rd Edition,” Butterworth-Heinemann, pp. 1-40, 1998.
-  Japan Society for Technology of Plasticity (Eds.), “Bending, Processing Technology of Plastics,” pp. 229-230, Corona Publishing, 2016 (in Japanese).
-  T. Hashimoto, “Processing Technology of Transparent Packaging Box and Related Problems,” CARTON-BOX, Vol.23, pp. 44-45, 2004 (in Japanese).
-  H. Ishihara, “Fundamental and Application of Plastics Films,” pp. 33-52, Converting Technical Institute, 2010 (in Japanese).
-  H. Jmal, N. Bahlouli, C. Wagner-Kocher, D. Leray, F. Ruch, J. N. Munsch, and M. Nardin, “Influence of the grade on the variability of the mechanical properties of polypropylene waste,” Waste Management, Vol.75, pp. 160-173, doi: 10.1016/j.wasman.2018.02.006, 2018.
-  B. Jiang, L. Cao, and F. Zhu, “Dynamic tensile behavior of polypropylene with temperature effect,” Composites Part B: Engineering, Vol.152, pp. 300-304, doi: 10.1016/j.compositesb.2018.08.133, 2018.
-  S. Okuda and W. S. Choi, “Mechanism of Cutting Fracture of Polypropylene by Impact on Wedge-Shaped Target,” J. of Chemical Engineering of Japan, Vol.14, No.2, pp. 149-153, doi: 10.1252/jcej.12.383, 1981.
-  W. Bauer and D. Wüstenberg, “Fracture Behavior of Polypropylene under Dynamic Cutting and Shearing Action in Granulators,” Chemical Engineering & Technology, Vol.25, No.11, pp. 1047-1051, doi: 10.1002/1521-4125(20021105)25:11<1047::AID-CEAT1047>3.0.CO;2-6, 2002.
-  H. Hojo, “Punchability of Plastics,” Koubunshi, Vol.14, No.8, pp. 685-692, doi: 10.1295/kobunshi.14.685, 1965 (in Japanese).
-  H. Hojo, H. Masumori, Y. Kageyama, and T. Takahashi, “Shearing of Thermoplastic Polymer Sheets at Room Temperature,” J. of the Japan Society for Technology of Plasticity, Vol.9, No.88, pp. 304-314, 1968 (in Japanese).
-  S. M. Zebarjad, R. Bagheri, A. Lazzeri, and S. Serajzadeh, “Fracture behaviour of isotactic polypropylene under static loading condition,” Materials & Design, Vol.24, No.2, pp. 105-109, doi: 10.1016/S0261-3069(02)00130-9, 2003.
-  J. Snyder, A. Hiltner, and E. Baer, “Analysis of the wedge-shaped damage zone in edge-notched polypropylene,” J. of Materials Scienece, Vol.27, No.7, pp. 1969-1977, doi: 10.1007/BF01107226, 1992.
-  P. Mitsomwang, S. Nagasawa, S. Chaijit, M. Fujikura, and Y. Mutoh, “Effect of Underlay Stiffness on Cutting Profile of Polycarbonate Sheet during Wedge Indentation Process,” J. of Advanced Mechanical Design, Systems, and Manufacturing, Vol.6, No.7, pp. 1168-1179, doi: 10.1299/jamdsm.6.1168, 2012.
-  A. Yamamoto, S. Singprayoon, S. Nagasawa, and S. Chaijit, “Bending behavior of polypropylene sheet subjected to two-line wedge indentation,” Trans. on GIGAKU, Vol.4, No.1, 04003/1-9, 2017.
-  P. Mitsomwang, S. Nagasawa, H. Kuroiwa, and Y. Fukushima, “Deformation Analysis of Silicone Rubber Sheet Subjected to Keen WC Blade Indentation,” Int. J. Automation Technol., Vol.8, No.5, pp. 761-772, doi: 10.20965/ijat.2014.p0761, 2014.
-  G. Matsumoto and T. Ishihara, “Nakayama’s Cutting Rules and Their Best Choice,” J. of Packaging Science & Technology, Japan, Vol.25, No.5, pp. 241-250, 2016 (in Japanese).
-  Research Group of Die-Cutting Technology on Paperboard and Composite Materials (Eds.), “Mechanics and Technology of Form Cutting for Paperboard-Like Materials Processing,” pp. 80-83, Taiyo Shobo, 2016 (in Japanese).
-  J. Grunzweig, I. M. Longman, and N. J. Petch, “Calculations and Measurements on Wedge-Indentation,” J. of the Mechanics and Physics of Solids, Vol.2, No.2, pp. 81-86, doi: 10.1016/0022-5096(54)90002-2, 1954.
-  H. Miyairi, “Chapter 4, Fracture of Polymeric materials,” Materials Science Society of Japan (Eds.), “Materials and Fracture,” pp. 120-121, SHOKABO, 1989 (in Japanese).
-  M. Nishida, R. Natsume, N. Fukuda, and H. Ito, “Comparison between compressive properties of Polypropylene/Degra-Novon blends after outdoor weathering tests and accelerated weathering tests,” J. of the Japanese Society for Experimental Mechanics, Vol.13, Special issue, pp. s160-s166, 2013.
-  M. I. Okereke, C. P. Buckley, and C. R. Siviour, “Compression of polypropylene across a wide range of strain rates,” Mechanics of Time-Dependent Materials, Vol.16, No.4 pp. 361-379, doi: 10.1007/s11043-012-9167-z, 2012.
-  The Society of Materials Science (Eds.), “Strength and Fracture of Materials,” The Society of Materials Science, pp. 80-82, 2009 (in Japanese).
-  R. P. Kambour, “A review of crazing and fracture in thermoplastics,” J. of Polymer Science: Macromolecular Reviews, Vol.7, No.1, pp. 1-154, doi: 10.1002/pol.1973.230070101, 1973.
-  I. Narisawa, “Deformation mechanism and fracture theory of polymers,” Koubunshi, Vol.42, No.5, pp. 384-388, doi: 10.1295/kobunshi.42.384, 1993 (in Japanese).
-  S. Nagasawa, Y. Fukuzawa, T. Yamaguchi, M. Murayama, D. Yamaguchi, and I. Katayama, “Effects of blade tip shape on thread dross occurrence in paperboard die cutting,” J. of the Japan Society for Technology of Plasticity, Vol.43, No.498, pp. 624-628, 2002 (in Japanese).
-  K. Asai, “Improve the efficiency of the Makeready,” J. of Packaging Science & Technology, Japan, Vol.25, No.5, pp. 251-259, 2016 (in Japanese).
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