Starting from Forty-Six Hours

A fax from an old German factory stopped solder foil and detectors, and the interface diffusion process was stuck at a 3% pass rate. The protagonist Han Yan used a set of curve parameters (heating to 4 degrees for one minute, adding two steps, and keeping the temperature at 780 degrees for two hours) to move the qualified parts from "one out of three furnaces" to "seven out of one furnace". The cold data chain was pushed all the way to "halve the number of furnaces, eight times more pieces, and 900 pieces a year." The demand is 800 pieces.