【摘要】 利用激光可实现对预制Ｖ型切口根部一定深度层内的淬硬，从而大大提高了材料的屈服强度，降低了断裂韧性值Ｋ＿（１ｃ），减少了疲劳断裂周次；并且实现了塑性较好材料的韧性断裂到脆性断裂的转化，降低了断裂能耗，提高了断料效率和断口质量。更多还原

【Abstract】 Through the hardening of V-notch root to a certain degree by Laser process,theyield strength of material is increased,the fracture toughness K_1c and the fatigue fracturecycle index can be decreased.As a result,plastic materials exhibit the transformation fromductile fracture to brittle fracture with low fracture energy and the improvement of stock-fracture efficiency and the fractured surface quality.更多还原