🔌 Reflow Oven Solder Profile: Lumped Thermal Lag and Time Above Liquidus (2D)

Side view of a printed circuit board travelling through a six-zone reflow oven. Set conveyor speed, zone temperatures, heat-transfer coefficient and board thickness, and watch the board temperature follow the oven. Ramp rate, soak time, peak temperature and time above the lead-free solder liquidus come from a lumped thermal model compared with a one-dimensional conduction check, with four in-page numerical checks. A process companion to the 3D semiconductor packaging twin.