Mitsubishi Materials Corporation ("MMC") has developed MSP™5-SSH (Super Spring Hard), a new ultra-high-strength copper alloy that meets growing market demands for smaller, more powerful electronic devices. The new alloy combines tensile strength in the 1 GPa (1,000 MPa) class with electrical conductivity of 43% IACS, enabling further miniaturization of electronic components while supporting higher current capacity. The material is expected to contribute to improved performance in AI servers, robotics applications, automotive equipment, and other next-generation electronic devices.

 

■Development Background

 

MMC began full-scale production of MSP™5 in 2021. MSP™5 is a solid solution strengthened (*1) copper alloy containing magnesium as an alloying element and is known for its excellent balance of strength, electrical conductivity and formability. In 2025, MMC expanded the lineup with MSP™5-ESH (Extra Spring Hard), a higher-strength grade designed for demanding electronic component applications.
In recent years, electronic components used in automotive applications, industrial equipment, robotics and data center equipment, including AI servers, have rapidly become smaller and more advanced.
Accordingly, materials used for electronic components are increasingly required to achieve higher strength while maintaining high electrical conductivity.
To address these requirements, MMC developed MSP™5-SSH. The alloy maintains the high conductivity of the MSP™5 series while achieving 1 GPa-class strength. This combination contributes to component miniaturization, increased current-carrying capability, reduced heat generation, and lower power loss in electrical terminals and connectors.
(*1) A strengthening mechanism in which alloying elements are dissolved into the metal matrix to improve mechanical properties.

 

■Technical Features

 

1. Combines 1 GPa-Class Ultra-High Strength with High Electrical Conductivity

MSP™5-SSH combines 1 GPa-class tensile strength with electrical conductivity of 43% IACS. By significantly enhancing strength while preserving the high conductivity of the conventional MSP™5 series, the alloy contributes to the miniaturization of electronic components and supports higher current-carrying capacity.
In addition, MSP™5-SSH can be considered for applications where high-strength copper alloys such as beryllium copper and titanium copper have traditionally been used. Its excellent conductivity helps reduce heat generation and minimize power loss in terminals and connectors.

 

2. Excellent Formability Despite Ultra-High Strength

Although high-strength materials generally present challenges during forming operations, MSP™5-SSH retains the excellent formability characteristic of the MSP™5 series.
The alloy can achieve a minimum bend radius of R = 0 in box-bending processes used for terminal production. It also provides excellent dimensional accuracy in stamping operations while suppressing burr formation, enabling stable mass production of complex-shaped components.

 

3. Reduced Environmental Impact Through a Simplified Manufacturing Process

As a solid solution strengthened copper alloy, MSP™5-SSH does not require the complex heat-treatment processes typically associated with precipitation-strengthened (*2) copper alloys such as beryllium copper and titanium copper.
The simplified manufacturing process helps reduce energy consumption and CO₂ emissions while maintaining the excellent manufacturability characteristic of the MSP™5 series.
(*2) A method of strengthening a material by precipitating other atoms (solute atoms) in the matrix of parent atoms (solvent atoms).

 

■Position Within MMC's Strategy

 

The development of MSP™5-SSH is one of the initiatives supporting the Mitsubishi Materials Group's Medium-term Management Strategy, "Creating the Future through Resource Circulation."
As MMC continues its shift from "volume to value," the company is expanding its portfolio of high-value-added products. MSP™5-SSH is positioned as a high-performance material that supports the continued evolution of electronic devices and is expected to see growing adoption in automotive, industrial equipment and AI server-related markets.
MMC will continue creating New Materials and supplying unique, high-performance materials and products as it works to realize Our Commitment: "For people, society and the earth, circulating resources for a sustainable future."

 

[Related information]

Press release (September 25, 2025)
New High-Strength Copper Alloy MSP™5-ESH Developed
URL: https://www.mmc.co.jp/corporate/en/news/2025/news20250925.html

 

Press release (April 18, 2024)
Received the Science and Technology Award (Development Category) for the First Time in 2024 Commendation for Science and Technology by the Minister of Education, Culture, Sports, Science and Technology
URL: https://www.mmc.co.jp/corporate/en/news/2024/news20240418.html

 

Press release (May 20, 2021)
Start of Full-Scale Production of Copper Alloy "MSP5" for Automotive Small Terminals
URL: https://www.mmc.co.jp/corporate/en/news/2021/news20210520.html

 

About Mitsubishi Materials' Copper & Copper Alloy Products Business
URL: https://www.mmc.co.jp/corporate/en/business/copper/

 

"MSP" series introduction page on the Copper & Copper Alloy Products Business's website
URL: https://www.mitsubishi-copper.com/en/products/materials/msp/

 

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