Example 2: High-Strength Fastener for Automotive Assembly

Context:

You're a material specialist working for an automotive supplier specializing in engine components. You need to select the ideal material for high-strength bolts used in a critical engine assembly. These fasteners must withstand significant tensile loads to ensure the integrity of the engine block connection. Since engine compartments can experience vibrations, the material must also possess good ductility to prevent brittle fracture. Additionally, the company has set aggressive sustainability goals, requiring new components to have a demonstrably lower carbon footprint in their material production. All relevant mechanical properties, such as tensile strength and elongation, are considered at room temperature for design purposes.

Objective:

Find a material that offers high tensile strength (> 800 MPa) and good ductility (A > 10%) at room temperature, suitable for manufacturing robust fasteners, while also demonstrating a lower carbon footprint in its production and .

Fasteners are often manufactured by forging wires or bars, a process that enhances their strength and durability. This method involves shaping raw materials under extreme pressure and heat to achieve the desired form and function.

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1

Select Total Materia Mode

When beginning with a clean slate, explore the vast database of over 500,000 materials in Total Materia to identify the one that perfectly suits your requirements.

2

Select the desired form

Two options are available in this scenario:

• Option A: Search for materials reaching the desired strength after forging. You then ensure that the material is both forgeable and reaching the desired strength. In this case, we will set the desired form to "Forgings".

• Option B: Search for malleable materials in wire or bar form in order to forge them This option is valid, however the results might include materials which are not reaching the desired strength after forging. In this case, select

  • Wire and Long product as desired forms

  • Further you will also set Elongation >10% and Tensile strength > 800 MPa as if the material is stronger than your target in raw form it will at least retain this strength after the forging.

Option A will be followed for the rest of this exercise, feel free to try out the Option B on your own and tell us about your results.

The importance on form criteria can be decreased to 0.1 as long as it is kept mandatory to be fulfilled.

3

Strong enough material

Add a criterion requiring a minimum tensile strength of 800 MPa to ensure your fastener is sufficiently strong. Use the "higher is better" setting to prioritize stronger materials. Setting this as mandatory guarantees all selected materials meet the >800 MPa criterion. You can adjust the importance weight: use a value of 0.5 to keep some influence of strength, or decrease it to lessen its impact on the score.

4

Carbon Footprint

To emphasize environmental responsibility, include a criterion focused on the carbon footprint, quantified by the Climate Change GWP100 metric. Set this criterion with a "lower is better" target, ensuring priority is given to materials with the smallest environmental impact. By assigning this criterion an importance weight of 1, it becomes 2 times more influential than previously set criteria, highlighting the commitment to reducing climate impact while maintaining product performance and cost objectives.

5

Cost

Let's not forget to put a target on the cost of the material. Similar to the carbon footprint, set the cost criterion with a "lower is better" target to help prioritize economical materials without compromising on other important factors. Assign an importance weight of 1 to this criterion to ensure it is factored significantly in the selection process, balancing performance with financial sustainability.

6

Your manufacturing site

Running the algorithm at this stage, will get you a lot of materials from everywhere around the world. Lets consider that your production site is located in India. We will then select materials either by their regional availability or directly following Indian Standards IS which will ensure sourcing your materials locally.

Define Standard IS as a criteria.

7

Automotive Industry

When manufacturing parts for the automotive industry, one critical requirement is compliance with the Global Automotive Declarable Substance List (GADSL). This list outlines substances that are of particular concern for automotive parts and must be reported if used. To ensure compliance, add GADSL as a criterion in your materials selection process, setting it as "mandatory" to guarantee that only compliant materials (with no declarable substances) are considered.

Decrease the importance to 0.1 so that the overall score continues to prioritize key constraints: cost efficiency and minimal carbon footprint.

Going Further

Utilizing the plotting functions such as biplots can be incredibly beneficial for visualizing key relationships, like Tensile Strength versus Carbon Footprint or Cost. By plotting these criteria against each other, you can easily identify materials that perform well in both categories, thus making data-driven decisions more straightforward. Furthermore, the ability to modulate the importance of each criterion allows you to see how adjustments might affect the ranking and selection of materials. This dynamic approach aids in optimizing material choices to align with your specific goals, whether they be environmental, economical, or performance-centric.