SPE Library

Advances in Thermoplastic Composites Using CBT

Fred Deans, September 2009

The use of cyclic-polybutylene terephthalate (C-PBT) for manufacturing high-performance composites is taking on new roles. Advances in injection molding RTM molding pultrusion and composite tooling are benefiting from the use C-PBT thermoplastic resins leading to the development of new C-PBT technologies and applications.

Alternative Methods to Enable the Powder Priming of SMC

Hamid Kia, September 2009

Previous work has shown that the newly developed SMC systems are powder-primer ready in straight-through operations. However after an extended stoppage in the operation – such as July shutdown – the success of the powder application depends on the severity of temperature ramp in the oven. To overcome this issue alternative methods are proposed such as 4 min. of preheating in the oven at 180°C or 3 min. of IR exposure.

The Influence of SMC Formulation Inner Panel Thickness & Bond Stand-Offs on Bond-Line Read-Through Severity

Kedzie Fernholz, September 2009

Two experiments designed to understand the relationship between material and process factors and bond-line read-through (BLRT) severity will be discussed. Regression analyses of the data collected in these experiments were able to establish relationships between the experimental factors and BLRT severity with at least 80% correlation.

Flexibility in the Direct Strand Moulding Compound (D-SMC) Process

Tobias Potyra, September 2009

In order to improve quality issues as well as to establish an integrated and continuous process for compression-moulded parts a direct processing technology has been developed. This presentation should demonstrate the flexibility of the new direct-SMC technology in terms of use of alternative and new raw materials and formulations.

Recent Advances in Class A Polyurethane Long Fiber Injection (LFI) Composites

Usama Younes, September 2009

Recent advances in related polyurethane chemistry have increased the commercial viability of the long fiber injection (LFI) process for producing very-large composite parts such as entry-door skins truck body and spa panels and recreational boat hulls. These advances enable the LFI process to achieve previously unattainable extended gel times on an open hot mold retain a relatively short demold time and form defect-free surfaces that can lead to the Class A surfaces required for large automotive body panels.

Composite Power-Train Components: Reducing Warranty Costs & Improving Part Quality

Toai Ngo & Mayur Shah, September 2009

Sheet-molding compound has been used in underhood applications and is extending its reach to drivetrain components. This presentation will show how vehicle manufacturers have reduced costs and improved quality through product designs that eliminate hardware enhance capability and improve system performance.

Automotive Composites Consortium Structural Composite Underbody

Libby Berger, September 2009

The Automotive Composites Consortium Focal Project 4 (ACC FP4) is a joint program between GM Ford and Chrysler to develop structural automotive components from composite materials. Part of this project is a structural composite underbody capable of carrying crash loads. Phase 2 of the project involves a full design of the underbody including design for durability and feasible component manufacturing and vehicle assembly scenarios.

BMC Composites: High Value Metal Replacement Material Alternative for Automotive Powertrain Applications

Jim Cederstrom, September 2009

Performance requirements for underhood components are increasing making historically used thermoplastics unsuitable for next-generation engines. The need for higher thermal chemical and mechanical resistance is opening the door to thermoset bulk-molding compounds (BMC) for critical metal-replacement opportunities successful examples of which will be presented.

Application of Digimat Micromechanical Modeling to Polymer Composites

Peter Foss, September 2009

DIGIMAT micromechanics-modeling software was evaluated to predict the nonlinear stiffness and strength properties of glass-filled nylon. In this particular case due to the high aspect ratio of the fibers the properties of reverse engineered effective actual matrix properties were needed to accurately correlate both the matrix" rather than theflow and transverse to flow stress-strain behavior."

Advanced Simulation of Fiber-Reinforced Automotive Radiator End Tanks by Capturing Anisotropic Material Properties

Suresh Shah, September 2009

This study aims to capture realistic anisotropic properties of a plastic material in a structural analysis. Moldflow software has been used to obtain the fiber-orientation details for a plastic radiator tank. This fiberorientation output data have been transferred to the structural analysis software (ABAQUS using commercially available interface software (DIGIMAT). This integrated simulation technique helps in accurate prediction of burst pressure strength of the plastic tank.

Material Characterization & Modelling of Long Glass-Fiber Composites

Matthew Marks, September 2009

Modeling the stiffness of parts injection molded from long-fiber materials is similar to yet different from behavior using short-fiberfilled materials. This work discusses the effects of various modeling assumptions and methods on stiffness predictions using a coupled Moldflow-Digimat-Abaqus analysis methodology.

Fatigue Properties of Injection Molded 33% E-Glass Fiber Reinforced Polyamide-66

Shivanand Sankaran, September 2009

This paper presents the effects of melt temperature injection pressure hold pressure and injection speed on the tensile and fatigue properties of 33-wt% E-glass fiber-reinforced polyamide-66. It was observed that these process parameters had a greater influence on the fatigue properties than on the tensile properties. Melt temperature had the greatest effect followed by injection pressure. Both hold pressure and injection speed had smaller but significant effects on the fatigue life.

Identification Selection & Development of Composite Test Standards - A Case Study from the Development of a Design Standard for Composites

Ellen Lackey, September 2009

This paper examines the identification selection and development of appropriate composite test methods as required in the composites design process. Examples from the development of a load and resistance factor design (LRFD) standard for pultruded composites are presented. The issues addressed for this case study discussion are applicable to any segment of the composites market that is looking to establish design procedures or develop design standards.

Study of Braided Composites for Energy Absorption

Andy Rich, September 2009

The goal of this research project was to provide data to build FEA tools and to improve the understanding of braiding technology in order to expand predictive abilities for post-yield behavior of carbon fiber products braided with multiple hybrid fibers.

Mesoscopic Finite Element Simulation of the Compression Forming of Sheet Molding Compound Woven-Fabric Composites

James Sherwood, September 2009

This paper describes a mesoscopic approach of using beam and shell finite elements to model the forming of composite parts using an SMC woven fabric. Nonlinear constitutive models are implemented in ABAQUS/Explicit via user-defined material subroutines to describe the shear and tensile mechanical behavior of the woven fabric. Both single-ply and multiple-ply layups are modeled.

Using a New Composite Energy-Absorber Bumper to Improve Automotive Crashworthiness

Siavash Taher, September 2009

An Investigation of ‘Green’ Class-A SMC

Thomas Steinhäusler, September 2009

Saturated- and unsaturated-polyester resins containing glycols made from renewable or recycled sources are being developed as a way to become less dependent on petroleum-based glycols. In this study SMC performance of standard-density Class A automotive SMC containing polyester resins produced from petroleum-based glycols was compared to standard-density Class A automotive SMC containing polyester resins produced from renewable-source glycols. The evaluation included processing aesthetics and adhesion performance. Finally a new low-density Class A automotive SMC containing polyester resins produced from renewable-source glycols will be introduced.

Bio-Based Polymers from Soy Chemistry

Dwight Rust, September 2009

Research on the use of soybeans to produce polyurethane polyols unsaturated polyester resins and thermoplastic fibers has been funded by the United Soybean Board (USB). The USB funds a wide range of activities including research and development of new industrial products made from soy. These developments have resulted in new patented technology. Commercialization of this technology has resulted in the production of unsaturated-polyester resins for fiberglass-reinforced composites and urethane polyols for polyurethane foams. The commercial applications of these bio-based polymers are found in a wide range of applications in the transportation markets.

Development of Injection Moldable Composites Utilizing Annually Renewable Natural Fibers

Ellen Lee, September 2009

In order to advance the commercialization of natural fiber reinforced plastics for automotive use a partnership was formed between academia natural fiber processor material supplier and OEM. This partnership improved the communication along the supply chain and resulted in optimized material properties to meet OEM specifications and application part performance. Several products have been developed that meet current material specifications offer significant weight savings over conventional mineral- and glass-reinforced composites and are competitively priced.

Renewably Sourced Engineering Polymers for High-Performance End-Use Applications

Richard Bell, September 2009

External trends have continued to drive end users in consumer and industrial applications to seek renewably sourced and sustainable solutions to use in more and more demanding applications. To meet this need a portfolio of renewably sourced engineering materials was developed. The products are designed to provide performance and functionality equivalent to or better than today’s petroleumbased materials while reducing the environmental footprint. The portfolio includes glass-reinforced thermoplastic grades for high strength and stiffness.