Strips

NGK Berylco offers custom-sized beryllium copper strips and coils tailored to your specific requirements and constraints. Each Berylco alloy type provides a unique combination of properties. The choice of alloy depends on your performance criteria in terms of electrical and mechanical characteristics, reliability, durability, miniaturization, and cost-efficiency.

Our experts are here to help you make the right selection!

For the standard CuBe 1.9 alloy (1.8–2% Be), the metal is heated between 720°C and 860°C. At this stage, the beryllium is essentially “dissolved” in the copper matrix (alpha phase). A rapid quench to room temperature retains this solid solution structure.

At this point, the material is very soft and ductile and can be easily cold-worked by drawing, rolling, or cold heading.

The solution annealing process is carried out at our facility and is generally not performed by the customer. Temperature, dwell time, and quench rate are critical parameters to control grain size and hardness.

Precipitation hardening significantly increases the material’s strength. This reaction is typically carried out at temperatures between 260°C and 540°C, depending on the alloy and the desired properties. During this cycle, dissolved beryllium precipitates as a beryllium-rich (gamma) phase within the matrix and along grain boundaries.

It is the formation of these precipitates that leads to the substantial increase in mechanical strength. The final properties achieved depend on both the aging temperature and the time at temperature.

It is important to note that beryllium copper does not age-harden at room temperature. NGK Berylco products are available in either cold-worked or heat-treated condition.

Age-Hardenable (Before Aging) – This condition refers to material that can reach its highest mechanical properties through a simple heat treatment performed after stamping or forming. Proper aging will typically double the strength level.

Fully Aged (After Standard Aging) – This temper indicates that the material has undergone optimal heat treatment to achieve maximum mechanical strength.

Mill-Hardened – These tempers have been pre-aged under controlled conditions at the mill to deliver mechanical properties between the cold-worked and fully aged states. They can be used as-is without further heat treatment by the customer and offer excellent formability. Mill-hardened tempers are also ideal for manufacturing robust miniature parts, minimizing the risk of dimensional distortion during any final aging process.

Alloys – High Formability at Equivalent Strength

B25 Mill-Hardened ‘Type-B’ and ‘Type-S’ Alloys

The new Berylco 25 mill-hardened ‘Type-B’ and ‘Type-S’ tempers have been specifically developed to improve formability.

The bend radius ratio (R/t) of ‘Type-B’ is half that of the standard mill-hardened alloy.

The bend radius ratio (R/t) of ‘Type-S’ is one-quarter of the standard, thanks to controlled grain size refinement.

These mill-hardened alloys are delivered in a pre-aged, hardened state. They allow customers to use the material as-is, without the need for any additional heat treatment..

Comparison of bend test results between standard B25 HM and the new B25 HMB (‘Type-B’ temper).

The images show the outcome of a 90° bend (longitudinal direction, R/t = 1.0, thickness 0.2 mm). Microcracks are visible on the B25 HM sample, while the B25 HMB sample shows no cracking.

The new ‘Type-B’ and ‘Type-S’ mill-hardened tempers offer excellent formability, while maintaining the same tensile strength of 1000 N/mm².

Typical R/t value for 0.15 mm thick sample.