In ‘TechWorld: Engineering Materials’, Year 10/11 students are learning about the quenching and annealing processes, using stainless steel hair pins.
Students heat the pins until they’re red hot and then quench them in either oil, water, or anneal in air. The various pins are bent until they snap, and then the angles at which they break are measured with a protractor. Students discover that the process of quenching in different media can alter a material’s properties. Although this topic is interesting, the focus of this practical investigation was to hone our students’ scientific data collection/representation skills.