Full definition
3M VHB (Very High Bond) — a family of double-sided acrylic foam tapes that provide permanent structural bonding between two surfaces, replacing mechanical fasteners (screws, rivets, welds) in many applications. The closed-cell acrylic foam core (0.25-3.0 mm thick) is viscoelastic — it absorbs stress, distributes loads, damps vibration, and accommodates differential thermal expansion between dissimilar materials. Tensile strength: up to 45 N/cm width. Long-term holding power: designed for permanent bonds with no creep under sustained load. Temperature range: -40 to +90°C (standard grades), +150°C (high-temperature grades). Substrates: metals (excellent), glass, powder-coated surfaces, and many plastics (surface energy >30 mN/m required — PE/PP need flame or plasma treatment). Advantages over mechanical fasteners: no holes (preserves substrate strength and waterproofing), distributes stress (no stress concentration), absorbs vibration, and provides cleaner aesthetics. Key application requirement: surfaces must be clean (IPA wipe), dry, and >15°C for application. Full bond strength develops over 72 hours. Applications: architectural panel bonding (curtain wall), automotive trim and emblems, electronics assembly, sign mounting, and industrial equipment panels. Per 3M VHB technical bulletins. Competitors: Tesa ACXplus, Nitto.