New release offers fatigue technologies for Composites and Adhesive Bonds

nCode, the leading brand of durability, test and analysis products offered by HBM, announced today the version 8 release of nCode DesignLife™, a leading solution for CAE fatigue analysis applications. Significant fatigue technologies introduced include thermo-mechanical fatigue, short fibre composite fatigue analysis, and adhesive bonds for vehicle structures, while also delivering substantial improvements in overall performance and calculation speed.

nCode DesignLife uses stress and temperature results from industry-standard finite element software and provides CAE durability simulation to estimate component life in these extreme operating conditions. Implemented methods include Larson-Miller creep and Chaboche for combined creep and fatigue. Creep calculations can also be performed from time histories of stress without an FE model. The required materials data can be provided through a Materials Testing service available at their ISO9001 certified laboratory. Building upon previous projects with industry partners investigating available thermo-mechanical fatigue (TMF) methods, this commercial software implementation in nCode DesignLife 8 provides cost-effective tools that can be used to solve real-world design problems.

Version 8 of nCode DesignLife also offers methods for predicting the fatigue of composite materials as a result of collaboration between HBM-nCode and e-Xstream engineering, provider of state-of-the-art material modeling platform, DIGIMAT. The initial focus of the DesignLife solution is in the area of engineering plastics, such as short fibre polymers, that are commonly used in the automotive industry. DIGIMAT determines the appropriate material parameters for a complete component, which can then be coupled with a finite element analysis. nCode DesignLife combines the calculated stresses together with specific fatigue properties to predict the fatigue lives of the whole component under loading conditions.

Methods for assessing the durability of adhesive bonds in lightweight vehicle structures are also now available in nCode DesignLife version 8. A fracture mechanics-based method is used, requiring relatively minor modifications to a typical vehicle body finite element model. The implemented method provides a safety factor assessment of each joint by comparing the calculated maximum strain energy release rate to the threshold required for crack growth. The theoretical basis of the method was developed as part of a project conducted by the Volvo Group and the testing and software implementation was carried out as part of the “Bonded Car” collaborative research project, the partners including Jaguar Land Rover, Coventry University and Warwick University. The project was co-funded by the Collaborative Research and Development programme of the Technology Strategy Board, an executive non-departmental public body in the United Kingdom.

Speed of analysis is significantly improved in DesignLife 8 and two processing cores can also be used as standard. This results in up to four times faster analysis of the base product over previous versions on multi-processor computers, with near linear speed-up with additional processing cores.