304不锈钢超高周疲劳试验裂尖马氏体相变

Austenite-martensite Transformation Occurs in Crack Pointed end of 304 Stainless Steel During the Ultrasonic Fatigue Test

采用超声疲劳试验技术对304不锈钢进行了超高周疲劳试验,并用扫描电镜对疲劳断口进行了分析。结果显示304不锈钢在Nf=8.60×108,σα=±206MPa的疲劳断口SEM形貌中的第一裂纹扩展区高倍放大像出现羽毛状片层结构,通过X射线衍射发现在奥氏体峰旁有铁素体峰出现。通过分析推测,304不锈钢超高周疲劳试验形变诱发马氏体相变。

Fatigue behavior of 304 stainless steel was studied with the ultrasonic fatigue testing,and with Scanning electron examine the fatigue crack fracture surface.The results showed that 304 stainless steel in the Nf=8.60×108,σα=±206Mpa SEM fracture morphology of fatigue crack growth in the first district high magnification appear as feathery lamellae,finding Austenite peak next to the ferrite peaks by X-ray diffraction.Analyses and comparison proved it true that Deformation induced austenite-martensite transformation occurs in 304 stainless steel.