Mild Carbon Steel Plate,Hot Rolled Carbon Steel Plate,Cold Rolled Carbon Steel Plate,Carbon Steel Plate,Carbon Steel Plates Shandong Rizhaoxin Metal Products Co., Ltd. , https://www.changyimetal.com
The above-mentioned laser-quenched gear was cut into a complete tooth profile, and stress tests were performed on the tooth surface at the root portion and the index circle. The stress test was performed on an X-350A X-ray stress analysis system. The measurement method is a method of tilting 7 methods. The fixed peak method is the cross correlation method, the radiation is CrKa, the incident angle is 045b, the 2H scanning start angle is 163.0b, the 2H scanning end angle is 148.0b, and the 2H scanning step is 0.20b.
The laser-quenched gear was cut transversely, and after grinding, polishing and 4 nitric acid alcohol solution, a scanning electron microscope sample was prepared and analyzed on an AMRAY-1000B scanning electron microscope.
The depth and hardness of the hardened layer of the gear laser phase transformation hardening process are the distribution curves of the microhardness of the hardened layer along the tooth depth of the gear on the two sides of the gear along the depth of the layer. The effective hardened layer depth of the gear is 1.4mm, and the surface hardness is HRC61. The right tooth surface is the first hardened tooth surface, and the left tooth surface is the rear hardened tooth surface. It can also be seen from the figure that the hardness distribution of the laser hardened gear is relatively uniform.
It can be seen that the stress state of the hardened layer of the laser hardened gear is pressure, the maximum value is -506 MPa, and the depth of the compressive stress is 1.41.5 mm. Since the surface enhancement of the gear laser belongs to the surface local quenching, the stress distribution is mainly organized by the tissue. The result of the transformation of the resulting tissue stress.
Martensite transformation occurs after laser quenching of the gear surface. With volume expansion, the volume expansion of the surface layer is pinned by the unconverted matrix, so that compressive stress is generated on the surface of the gear, and the matrix is ​​tensile stress. The depth of the compressive stress layer is consistent with the depth of the hardened layer.
Since the surface enhancement of the gear laser belongs to the local quenching of the surface, this stress distribution is mainly the result of the tissue stress caused by the transformation of the structure. Martensite transformation occurs after laser quenching of the gear surface, accompanied by volume expansion. At this time, the volume expansion of the surface layer is pinned by the unconverted matrix, so that compressive stress is generated on the surface of the gear, and the matrix is ​​tensile stress. The depth of the compressive stress layer is consistent with the depth of the hardened layer.
Laser process component organization and analysis