INSTRUMENTED IMPACT TESTING OF A GLASS SWIRL MAT-REINFORCED REACTION INJECTION-MOLDED POLYAMIDE BLOCK COPOLYMER (NBC)

被引:12
作者
KARGERKOCSIS, J
机构
[1] Institut für Verbundwerkstoffe GmbH, Universität Kaiserslautern, Kaiserslautern, D-6750
关键词
D O I
10.1002/app.1992.070450910
中图分类号
O63 [高分子化学(高聚物)];
学科分类号
070305 ; 080501 ; 081704 ;
摘要
The fracture behavior of a reaction injection-molded (RIM) polyamide block copolymer (NBC) reinforced with a continuous glass strand mat (swirl mat) was studied in instrumented high-speed impact-bending tests. Investigations were carried out on Charpy and Izod specimens of different size and notching direction to elucidate specimens' size effects. From the tests performed at ambient temperature and -40-degrees-C, fracture mechanical parameters (fracture toughness, fracture energy) and E-modulus were derived. Changes observed in the above parameters of the matrix were attributed to a molding-induced skin-core morphology. Both fracture toughness and energy of the composites depended strongly on the type, i.e., on the ligament width (W) and length-to-span ratio (L0/L) of the specimens. Reliable fracture mechanics data can be determined in three-point bending when W > 12 mm and L0/L > 1.7 for the specimens. The fracture toughness and E-modulus increased monotonously, whereas the fracture energy reached a plateau as a function of fiber mat content. Their values were only slightly influenced by the temperature. It was also shown how molding- and machining-induced flaw size can be defined. The failure mode of the materials was studied by fractography and the failure events were summarized in a model and discussed.
引用
收藏
页码:1595 / 1609
页数:15
相关论文
共 23 条
[11]   EFFECTS OF PROCESSING INDUCED MICROSTRUCTURE ON THE FATIGUE CRACK-PROPAGATION OF UNFILLED AND SHORT FIBER-REINFORCED PA-6 [J].
KARGERKOCSIS, J .
COMPOSITES, 1990, 21 (03) :243-254
[12]  
KARGERKOCSIS J, 1991, DURABILITY OF POLYMER BASED COMPOSITE SYSTEMS FOR STRUCTURAL APPLICATIONS, P158
[13]  
KARGERKOCSIS J, IN PRESS J POLYM ENG
[14]  
KNAKAL CW, 1987, ASTM STP, V936, P44
[15]  
MACOSKO CW, 1989, RIM FUNDAMENTALS REA, P212
[16]   IMPACT FRACTURE-BEHAVIOR OF CONTINUOUS GLASS FIBER-REINFORCED NYLON-6 [J].
OTAIGBE, JU ;
HARLAND, WG .
JOURNAL OF APPLIED POLYMER SCIENCE, 1989, 37 (01) :77-89
[17]   DETERMINATION OF FRACTURE PARAMETERS FOR POLYMERS IN IMPACT [J].
PLATI, E ;
WILLIAMS, JG .
POLYMER ENGINEERING AND SCIENCE, 1975, 15 (06) :470-477
[18]   RANDOM GLASS MAT REINFORCED THERMOPLASTIC COMPOSITES .4. CHARACTERIZATION OF THE TENSILE-STRENGTH [J].
STOKES, VK .
POLYMER COMPOSITES, 1990, 11 (06) :354-367
[19]   RANDOM GLASS MAT REINFORCED THERMOPLASTIC COMPOSITES .1. PHENOMENOLOGY OF TENSILE MODULUS VARIATIONS [J].
STOKES, VK .
POLYMER COMPOSITES, 1990, 11 (01) :32-44
[20]   CHARACTERISTICS OF CYLINDRITIC CRYSTALLIZATION OF POLYPROPYLENE [J].
VARGA, J .
ANGEWANDTE MAKROMOLEKULARE CHEMIE, 1983, 112 (FEB) :191-203