As engineering materials evolve, designers increasingly face challenges when fastening into magnesium alloys, aluminium die-castings, zinc die-castings, printed circuit boards, and thermoset composites. Staying reliable demands fasteners for special materials that compensate for softness, brittleness, or low shear strength in the host material. These fasteners bridge the gap by providing hardened threads or embedded locking in otherwise unsuitable substrates.
PRODUCT INDEX
PRECISION HARDENED INSERTS & STUDS
PHI
These fasteners have been designed to provide a hardened steel thread to resist tensile and torsional loading in the softer aluminium and zinc based diecastings.
HARDENED STEEL SCREW-SERTS
SCT
The Screw-Sert range of fasteners have been designed to provide a hardened steel thread in the softer aluminium and zinc based diecastings, magnesium and thermosetting plastics.
PRINTED CIRCUIT BOARD FASTENERS
PCBR/SCBR
These fasteners have been designed to provide a metallic deep tapped thread into resin based printed circuit boards.
Core Types of Fasteners for Special Materials
Hardened Inserts & Studs
Precision inserts and studs are built from hardened steel and are designed to be installed into soft die-castings or special substrates. These inserts deliver high tensile and torsional strength, allowing repeated service and resisting wear, even in fragile metals. The external spiral knurled pattern cuts into the parent body and helps reduce radial stress.
Screw-Sert Range
A key subset of fasteners for special materials, the Screw-Sert family, is engineered to establish hardened steel threads inside soft aluminium, zinc alloys, magnesium and thermoset plastics. These fasteners eliminate the need for tapping operations in weak substrates. They combine external cutting features and broaching action to ensure robust thread formation.
PCB & Resin Board Fasteners
When fastening into resin-based printed circuit boards or FR-4 type materials, specialized fasteners for special materials provide metallic deep-tapped threads. These fasteners must avoid cracking brittle board material, so the installation forces are carefully controlled and the fastener geometry is designed to minimize stress at edges.
Design & Engineering Guidelines
Joint Design
Ensure the mating component contacts the face of the insert to distribute load.
Avoid excessive torque loads directly on the fastener; use washers or flanges to spread load.
Hole Preparation
Holes can be drilled or cored; if cored, include a taper of ~0.5° inclusive.
The hole diameter should refer to the insert’s bottom point (i.e. the deepest seating point).
Blind holes require depth at least 1.2× the insert length.
Wall Thickness & Substrate Considerations
- As a rule, wall thickness should not fall below the nominal thread diameter; special materials like magnesium may demand modified fasteners or support ribs.
- In thin walls or exotic alloys, consult test data or the manufacturer to specify custom fasteners for special materials.
Installation & Best Practices
Use a squeeze press or controlled force, not shock loading (drop hammers).
Install inserts squarely and avoid side loads.
Countersink the top of holes (~60°) to prevent chipping.
Monitor and control axial pressure and rotational torque during installation.
Prototype and test under real-use conditions (vibration, thermal cycles, humidity).
Advantages & Applications
These fasteners let you dismantle, service or adjust assemblies in special materials without damage.
They support repeated re-footing, high torque, and high fatigue applications.
Ideal for aerospace, electronics housings, powertrain light-metal castings, and composite structures.