What Materials Are Used for Phone Frames?

Phone frames are primarily made from four main materials: aluminum alloy, stainless steel, titanium, and specialized plastics.

23:59 13 June 2025

When we pick up a smartphone, it feels solid, smooth, maybe a bit heavy – or surprisingly light. That feeling comes down to what materials are used for phone frames. Usually, brands choose custom cnc parts materials including phone frame materials based on performance, cost, and user experience. And each option, from metal to plastic, has a specific purpose in modern phone design.

Let’s break down the most common options for materials that are used for phone frames and how they shape a phone’s design, performance, feel, and durability.

1. Aluminum Alloy

According to Statista there are over 7.2 billion smartphones worldwide and aluminum is the dominant material for phone frames for mid-range and flagship models. It’s lightweight, durable, and has good heat dissipation. 

Aluminum is easy to machine for custom cnc parts like phone frames, which makes it a top choice for mass production. It also allows for sleek finishes through processes like anodizing. However, it can dent or scratch more easily than harder materials.

Here’s a breakdown of phones built with aluminum alloy frames.

Brands	Phone Models	Notes
Apple	iPhone 6/6s/7/8/SE (2nd, 3rd Gen), iPhone XR/11/12/13/14/15 (non-Pro)	Standard iPhone models; lightweight, durable
Samsung	Galaxy S21/S22/S23 (non-Ultra), Note 20 (base model), S20 Fan Edition	Used in both flagships and mid-range; Note 20 base model has aluminum frame; S20 FE uses aluminum
Google	Pixel 4/5/6/7/8	Anodized aluminum; blend of weight and heat dissipation
OnePlus	OnePlus 9/10/11	Offers sleek design and better cooling
Sony	Xperia 10 series	Mid-range series with aluminum shells

2. Stainless Steel

This material is heavier than aluminum but much stronger and more resistant to scratches. According to data cited on Wikipedia, stainless steel has a much higher tensile strength than aluminum, typically ranging from 515 to over 1300 MPa depending on the grade. This strength, along with its corrosion resistance, makes it a common choice for high-end smartphone frames and watch bodies.

However, the frames made from stainless steel are harder to process, which drives up manufacturing time and cost. Still, they providebetter rigidity, which is useful for phones with large displays. 

Here’s a breakdown of phones built with stainless steel frames.

Brands	Phone Models	Notes
Apple	iPhone X/XS/11 Pro/12 Pro/13 Pro/14 Pro	Polished finish, premium feel, more scratch-resistant
Samsung	Galaxy Note 20 Ultra	Used for its enhanced rigidity and premium feel
Vertu	Vertu Signature Touch	High-end luxury phones with steel bodies

3. Titanium

Titanium is lighter than stainless steel but just as strong. It resists corrosion and holds up well in extreme environments. Research from Unionfab, a specialist in advanced manufacturing, highlights that titanium alloy has a remarkable strength-to-weight ratio. This makes it well-suited for custom cnc parts such as smartphone frames.

On the flip side, Titanium is not easy to work with – it’s tough on tools and requires slower, more precise machining. That makes it expensive. But for brands wanting to stand out, it’s worth the cost!

Here’s a breakdown of phones built with titanium frames.

Brands	Phone Models	Notes
Apple	iPhone 15 Pro/15 Pro Max	First mainstream models with titanium frame
Essential	Essential Phone PH-1	Titanium and ceramic construction
Turing Robotics	Turing Phone	Experimental titanium + liquidmetal combo
Vertu	Vertu Signature (premium series)	Used in luxury titanium editionsCAT rugged phones (select internal frames)
CAT	CAT rugged phones (select internal frames)	Not visible, but used for structural strength

4. Specialized Plastics and Composites

Not all phones need metal. Polycarbonate and glass-filled plastics are often used in budget phones or specific use cases like rugged devices. Plastics are easy to mold, lightweight, and resistant to impact. They also don’t interfere with wireless signals, making them practical for internal frames or antenna areas.

Some brands mix plastic with fiberglass or carbon fiber for added strength. These materials are cheaper to manufacture and allow more flexibility in shape and color.

Here’s a breakdown of phones built with plastics and composites frames.

Brands	Phone Models	Notes
Samsung	Galaxy A12 / A14 / A32 / A52 / A53 / A72	Matte polycarbonate design
Motorola	Moto G Power / G Stylus / G Play	Budget-friendly durable builds
Nokia	Nokia XR20 / Nokia 5.3	Some with recycled plastic bodies
Fairphone	Fairphone 4	Modular and repair-friendly plastic build
Xiaomi, Realme, ASUS	Redmi Note 11 / Realme Narzo 50 / ASUS Zenfone Max series	Affordable phones with lightweight plastic frames

Things to Consider When Choosing a Frame Material

When picking the right material for custom cnc parts such as phone frames, there’s more to think about than just looks. Each material affects the phone’s weight, strength, signal quality, cost, and overall design. 

The balance between these factors can shape the user experience and impact how easy or expensive the phone is to build. Here are a few key points to weigh up when choosing a frame material:

• Weight vs. Strength: Titanium offers the best of both, but aluminum is more common due to its low weight and easier processing.
• Signal Performance: Plastics and composites allow for better wireless signal flow. Metal frames often require antenna cutouts or internal solutions.
• Cost of Production: Stainless steel and titanium are more expensive to work with. Brands aiming for volume often stick with aluminum or plastic.
• Design Flexibility: Plastic allows more freedom in shape and finish. Metal is better for a premium feel but limits flexibility.

Here’s different phone frame material comparison:

Material	Strength	Weight	Cost	Manufacture
Aluminum Alloy	Moderate to High	Lightweight	Moderate	Easy to machine; widely used in CNC and die casting
Stainless Steel	Very High	Heavy	High	Requires precision machining; often used in high-end models
Titanium	Extremely High	Moderate	Very High	Difficult to process; needs advanced CNC or forging
Specialized Plastics	Moderate	Very Lightweight	Low to Moderate	Easy to mold using plastic injection molding