1.Why is it difficult to stick?
Cold-rolled steel and ABS (acrylonitrile-butadiene-styrene copolymer) are two fundamentally different materials:
Cold-rolled steel: polar surface, high surface energy, hydrophilic.
ABS plastic: non-polar surface, low surface energy, hydrophobic.
This inherent difference prevents them from bonding naturally through intermolecular forces like two identical materials. Direct bonding would result in a lack of strength.
2.How well do the adhesive bonding processes work and how strong are the bonds?
Process: A layer of specialized structural adhesive (such as epoxy resin, modified acrylate, or polyurethane) is applied to the surface of the cold-rolled coil after cleaning, polishing, and possible chemical treatments (e.g., phosphating, passivation). This adhesive is then pressed and cured with the ABS sheet under precise pressure and temperature.
Key to Adhesion:
Surface Treatment: This is the most critical step. Oil and oxide layers on the surface of the cold-rolled coil must be thoroughly removed, and surface roughness and reactivity must be increased to create a mechanical interlocking and chemical bond, forming a "glue nail" effect.
Adhesive Selection: A specialized two-component adhesive with high adhesion to both metals and plastics must be selected.
Process Control: Curing pressure, temperature, and time must be strictly controlled according to process requirements.
Advantages: Wide applicability, uniform stress distribution, damping and vibration reduction, sound and heat insulation.
Disadvantages: Multiple process steps, curing time, and high requirements for environmental conditions and operation.
3.How effective is the hot-pressing composite process and how strong is it?
Process: A pre-made hot melt adhesive film or a special film with active groups is used as the interlayer. Through heating and pressurization, the interlayer melts and simultaneously bonds to both the metal and ABS.
Key to Bond Strength: Precise temperature and pressure control, and the compatibility of the interlayer material with both phases.
Advantages: Environmentally friendly (solvent-free), fast, suitable for continuous production (e.g., roll-to-roll lamination).
4.How well does the in-mold injection molding composite process achieve its desired strength?
Process: First, the pre-formed cold-rolled coil part is placed into an injection mold. Then, molten ABS is injected directly onto the metal surface, and after cooling, it is integrally molded.
Key to Strength:
Metal Part Pretreatment: Typically, micropores, undercuts, or grooves are created on the metal surface (through etching, laser engraving, or stamping) to form a strong mechanical interlocking structure (similar to an "anchor bolt" effect).
Sometimes a special adhesive coating is used.
Advantages: Highest bonding strength, high design freedom, capable of complex structures, and high production efficiency.
Disadvantages: High mold cost, only suitable for mass production of standardized products.
5.What are the performance characteristics after composite?
High Strength and Lightweight: Steel provides rigidity and strength, while ABS reduces weight.
Noise and Vibration Reduction: The intermediate polymer layer effectively dampens vibrations and absorbs noise.
Thermal and Electrical Insulation: The ABS layer provides excellent thermal and electrical insulation.
Design Flexibility: The ABS side is easy to surface treat (spraying, electroplating, texturing).
Corrosion Resistance: ABS completely covers the metal edges, isolating them from environmental corrosion.