7 Questions to Ask When Choosing a Material for Your Engineering Design

What influences a product's performance and reception? What makes a design a success or failure?

It all starts with your specified material. There are seven main factors that will affect a material's performance:

1. Function
2. Application
3. Environment
4. Interacting components or systems
5. Maintenance
6. Supply chain & manufacturing
7. Fabrications

Let's take a closer look at these considerations.

7 Questions to Ask When Choosing Your Material

1.  What's the function?

The first and most obvious question: What will your product be used for? Considerations here should include:

• Properties
• Performance-driven design vs. cost-driven design
• Life span
• Aesthetic needs
• Expectations from client or end user

Certain applications require or expect a certain kind of material. There may be notoriety or status associated with certain materials - for instance, stainless steel has a higher "quality" reputation than carbon steel, even though carbon steel is more appropriate in certain applications (and more affordable overall). 

2.  What are the requirements of the application?

Different industries have different requirements for their products. For some applications, if products fail to meet certain standards, there are serious consequences for both the company and the end user. Consider:

• Standards or legal requirements
• Ease of use
• Special needs
• Possible effects of material on end user
• Failure & consequences
• Additional manufacturing services needed to ensure legitimacy of product
  
  

3.  In what environment will it be used?

Environment greatly impacts the life span of a product. Certain metals do well in highly corrosive environments, while others require protective coatings to withstand small amounts of moisture. For a successful long-lasting product, your material needs to be tough enough for its environment. 

• Types of corrosion in environment
• Level of corrosion
• Possible chemical interactions that affect properties/structure
• Coatings or protective finishes required

For indoor, delicate, single-use, or other controlled applications, this won't be as much of a consideration.

4.  How will it interact with other components of its environment?

Is your design a fully functional end product? Is it a piece of a full product? Is it a component of a larger system? Consider:

• Surrounding materials
• Possible interaction with differing materials
• How to ensure your component doesn't fail first

5.  What kind of maintenance will the final product need?

Sometimes the end user is responsible for maintenance. Sometimes they have to call an expert for repairs. Sometimes there will be no maintenance or repair - just replacement when the product fails. Your material choice can affect maintenance and repair options for the end user. Consider:

• Ease, frequency, and cost of maintenance/repair
• Access to maintenance resources
• Common maintenance methods for the final product - how will your component hold up if it's made of X material?

6.  How will it affect your supply chain?

Material choice influences your product's supply chain. You can streamline production by choosing common materials, or use your material of choice to guide how you choose a vendor. Consider:

• Where it will be ordered from and/or manufactured - in America or outsourced
• Are you starting with raw materials that will need to be forged, extruded, or formed - this adds extra time, effort, and resource spend
• One-stop shop or multiple vendors (specialty materials may require specialty manufacturing)

7.  What fabrications will the product need?

Certain materials are better for certain fabrications. The physical properties of your chosen material influence weldability, how well it keeps its shape when bent, and how much scrap is produced from different fabrication methods. Consider which fabrications you'll need and match the best material for those operations.

• Ductility
• Thickness
• Malleability
• Strength
• Edging & placement
• Scrap from cutting fabrications or defects

That's a quick overview. If you're not sure where to start, or which material would be best, here are some additional resources:

Article: How Material Affects Tube Bending Quality

Article: Aluminum vs. Steel

Article: Top 5 Carbon Steel Tubing Applications & Industries