Materials for Precision Machined Parts: Properties and Selection Criteria

In the domain of precision manufacturing, precision machined parts are used across different applications in industries like aerospace, automotive, and electronics. Due to their importance, these parts must deliver the best accuracy and performance at all times. This is where a precision machine shop comes in. 

Materials used for precision machined parts play a vital role in determining the quality of this process. As does selecting the right precision machine shop partner. 

Depending on the final product, materials can range from metals to plastics. In this blog, we will discuss the properties and selection criteria for materials used in precision machined parts, including how your precision machine shop partner of choice can help. 

Machine Parts for Precision: Their Properties

You can choose from a range of materials for your precision machine parts. Let’s start with the most common metals that are used, along with their properties:

  1. Aluminum

Aluminum is a preferred metal for its mechanical properties. It is a very strong yet affordable material, making it ideal for precision machined parts. It is widely used for parts like automotive gears and shafts, aircraft fittings, and medical equipment.

Physical properties:

  • Medium strength at less than 500 MPa
  • Resistant to corrosion and high temperatures (less than 400 °C)

Mechanical properties:

  • Easier and faster to machine than other metals
  • Inexpensive and easy availability
  1. Cold Rolled Steel

Cold-rolled steel is popular for its high mechanical strength and durability. It is widely used for machinery parts, aircraft fittings, construction parts, and consumer electronics.

Physical properties:

  • High strength that increases the strength of the final product by 20%
  • High precision accuracy which makes it ideal for smaller parts.
  • Equipped for handling high tolerances.

Mechanical properties:

  • Medium-level machinability
  • Expensive than other materials
  1. Stainless Steel

Stainless steel is most popular for properties like high strength and hardness. It’s widely used across industries in automotive components, aircraft fittings, surgical equipment, chemical processing parts, and electronic housing.

Physical properties:

  • High hardness and chemical resistance
  • High strength at over 500 MPa
  • Resistant to temperatures over 500 °C
  • Resistant to corrosion

Mechanical properties:

  • High machinability
  • Inexpensive than other materials
  1. Brass

Brass is typically used in high-volume applications across industries. It is widely used in industries like automotive for mechanical parts and valves, architecture, healthcare (medical equipment), and consumer goods.

Physical properties:

  • Medium strength
  • Low resistance to temperatures below 250 °C
  • Natural resistance to corrosion

Mechanical properties:

  • High machinability
  • Readily available and cheaper than many materials

Many popular plastics are used, too.

This above list provides basic information and can be a good starting point regarding material selection in broader, more general terms. It provides a simple overview of some commonly used materials that could be used in precision machining.

 Before we cover this in the context of selecting the right precision machining partner, it’s important to note that there may be significant variances based on specific alloys, treatments, environmental factors, grades, required tolerances, machining processes, and the intended application’s demands.

In brief, the nuances in material properties can be more extensive and varied – this is just another factor that makes the selection of the right precision machined parts partner all that much more key.

Also Read- How Precision Machined Products Drive Innovation and Progress

Your parts: The Right Material and Precision Machine Shop

Depending on the type of part, you should select the material that best meets your needs. Here are some practices to follow as part of your selection process:

  1. Define your material requirements

To choose the right material, you should first know the properties that it should have. This can include its mechanical, thermal, and additional properties (if required). Consider factors like the purpose of your precision machined part and the environment in which it will be used.

  1. Consider the material design and engineering

Precision machined parts need fixed specifications to meet their quality objectives. Ensure that the chosen material design and engineering are designed to meet these specifications. For instance, consider engineering factors like stress distribution analysis.

  1. Consider the various grades of materials

Metals like aluminum and titanium are available in different grades, each having specific properties. If you are considering these materials, make sure to drill down to the specific grade that fits your requirements.

  1. Shortlist all the qualified materials

Before selecting the most suitable material, make sure you create a list of qualified materials that can fulfill your requirements. It’s not recommended to select a single material without considering the alternatives. 

Also Read:- The Role of Precision CNC Machine Shops in Illinois Thriving Manufacturing Sector


To summarize, precision machined parts are important to maintain the quality standards of many industries. Evaluating and selecting the right material is crucial for delivering accurate and durable parts. You have options. The choice is yours. 

Based in North America, Midwest Turned is a reliable manufacturer of precision machined components for various industries, including aerospace, medical, agriculture, and manufacturing. A precision machine shop with the right precision workforce, processes and machines to meet all your requirements – and needs. 

With our professional services and expertise, you are assured of the best quality products in precision manufacturing. Contact us today and request a free quote. Our team would love to respond to your queries.