What effect does dwell time have on heat input and bonding in spin welding?

What effect does dwell time have on heat input and bonding in spin welding?

• A. Longer dwell time does not affect bonding.
• B. Dwell time is irrelevant to heat input.
• C. Dwell time contributes to heat input and bonding; too long can cause burn-through.
• D. Dwell time only affects color.

Answer: (C)

Dwell time is the period the parts stay pressed together while heat is being generated at the interface. The longer this period, the more frictional energy is delivered into the interface, raising the temperature and allowing the molten layer to wet and fuse with the opposing surface. That helps create a stronger bond because the materials can interdiffuse and lock together as they cool and solidify under pressure. But there is a limit: if dwell time is too long, the heat can overshoot and cause burn-through or degradation of the material, weakening the joint or damaging the parts. If dwell time is too short, there isn’t enough heat or time for adequate bonding, resulting in a weak weld.

Dwell time is the period the parts stay pressed together while heat is being generated at the interface. The longer this period, the more frictional energy is delivered into the interface, raising the temperature and allowing the molten layer to wet and fuse with the opposing surface. That helps create a stronger bond because the materials can interdiffuse and lock together as they cool and solidify under pressure.

But there is a limit: if dwell time is too long, the heat can overshoot and cause burn-through or degradation of the material, weakening the joint or damaging the parts. If dwell time is too short, there isn’t enough heat or time for adequate bonding, resulting in a weak weld.