The front bumper of Tesla's model X, self-driving car, is showing signs of brittle fracture after reports of it cracking after drivers would bump into trash cans while parking in their garages. You are tasked with improving the ductility of the front bumper. Which process will increase the ductility of the steel? Described in the figure below is the current processing technique used. Temperature (°C) 800 700 600 500 400 Eutectoid temperature 1400 B 1200 1000 800 600 300 M(start) 50% Martensite Transformation 200 M+A 400 M(50%) M(90%) 100 200 Copy 10-1 10 102 103 104 105 Time(s) Upon cooling to 600°C, hold for 300 seconds and then cool to room temperature to produce a fully 100% pearlitic microstructure. Rapidly quench to the martensite start temperature, hold for 75 seconds and cool to room temperature. Upon cooling to 650°C, hold for 10 seconds and then oil quench to room temperature to obtain a 50-50 austenite-pearlite microstructure. Cool rapidly to 425°C (5 seconds), hold at that temperature for 10 seconds to obtain a 50-50 austenite-banite microstructure. Cool to room temperature. Temperature (°F)