Stress-strain behavior is at the core of all application development for design engineers. Envalior’s Stress-strain Tool helps you predict the stress-strain curve of our materials grades at any given temperature and humidity, ensuring the right conditions for your application without slowing down projects.
As a design engineer, who selects resins for various application types, it is important for you to validate and optimize an application design via simulations. To do so you need material data as an input, and basic stress-strain curve data is needed to simulate the stiffness and strength of an application.
With our Stress-strain Tool, we make it easy and quick for you to validate and optimize application designs. All you need to do is enter the grade selection, temperature and relative humidity of the application into the Tool.
Based on the input, our Stress-strain Tool accurately and instantaneously predicts the stress-strain curve, values of tensile modulus and strain-at-break, all at the selected conditions. You can do this for many of our materials and compare their performance in an efficient manner.
While our Stress-strain Tool currently considers the effects of temperature and relative humidity, keep in mind that there are other parameters that influence it too, such as strain rate, fiber orientation, etc. The Stress-strain Tool provides data at the standard (so-called quasi-static) strain rate, and for the standardized injection molded ISO5271A specimen.
During the concept and detailed design stages of product development, the Stress-Strain tool is most relevant. There will be requirements for the part in terms of stiffness and strength, and evaluating these requirements are best done by finite element (FE) simulations. The quality of the outcome is to a large extent governed by the availability and quality of the material data input, specifically the stress-strain curve.
Our Stress-strain Tool offers you a quick and efficient way to find out the stress-strain curve. Based on a few user inputs, the required stress-strain curve can be estimated by our Tool. Once you have the data you can download the curves into an Excel file and continue your project without any delay.
When compared to the traditional ways of measuring the stress-strain curve – asking a material supplier to measure the missing stress-strain curves or performing an interpolation to estimate the stress-strain curve for missing conditions, such as temperature and relative humidity – lead time is decreased and is less costly.
Also, we have measured stress-strain curves for many of our materials grades and conditions, such as temperature and relative humidity, which can be found in our datasheets and at plasticsfinder.com.
To build the Stress-strain Tool we collected in one database all stress-strain curves we measured for many of our materials grades. We then developed models based on polymer-physics to assess the effects of temperature, moisture, glass fiber content and glass fiber orientation on key descriptors of the stress-strain curve, such as modulus, stress-at-break, strain-at-break and curve shape.
Where needed we applied machine learning algorithms, resulting in our Stress-strain Tool predicting stress-strain curves with a high degree of accuracy within 10%.
We continue to improve the Stress-strain Tool by extending the number of grades and the available moisture conditions relevant for polyamides. In addition, we are also extending our modelling approach to include the effects of filler orientation and strain rate.
As part of our MaterialAdvisor, the Stress-strain Tool is part of our industry-leading intuitive digital tools and services. They were developed through close external partnerships with field experts and customers and evaluated by a review board of more than 100 engineers from a variety of companies across industries.
The key elements of the Envalior MaterialAdvisor include material performance calculators for creep, fatigue, thermal expansion, moisture diffusion, chemical resistance and heat aging. Plus, an online Failure Modes Advisor creates awareness of potential failures and provides mitigation actions.
Senior Design Engineer
Lucien Douven is responsible for the development of advanced CAE tools, based at the Envalior office in the Netherlands. He holds a PhD degree in Mechanical engineering, from Eindhoven University of Technology.
22 March 2023
Leveraging thermoplastic expertise to optimize system designs