江苏春晨电缆有限公司生产YFFBPGG扁电缆 春晨3*120，YFFBPGG扁电缆 春晨3*120，
如45号钢经亚火处理后疲劳极限为34.3MPa，经退火处理后为24.5MPa。经840℃淬火，420℃回火处理后为52.9MPa。由此可见45号钢经不同热处理后其机械性能有很大不同。
For example, the fatigue limit of 45 steel is 34.3mpa after sub fire treatment and 24.5mpa after annealing treatment. After quenching at 840 ℃ and tempering at 420 ℃, it is 52.9mpa. It can be seen that the mechanical properties of 45 steel are very different after different heat treatment.
环氧酚醛玻璃钢的疲劳特性：玻璃钢是一种多相材料，是一种纤维重合材料，是一种脆性材料（延伸率小于5%）
Fatigue characteristics of epoxy phenolic FRP: FRP is a kind of polyphase material, a kind of fiber coincidence material, and a kind of brittle material (elongation less than 5%)
玻璃钢的疲劳过程：玻璃钢的疲劳破坏过程是界面脱胶、树脂开裂和纤维断裂的综合过程。对于玻璃钢压板来说，破坏开始于与交变应力方向垂直的横向纤维束内，首先是界面个别点处的脱胶，脱胶沿着纤维方向发展，致使横向纤维束产生剥离。经过一段时间，树脂内产生裂纹，部件由半透明逐渐变为不透明，当裂纹进一步扩大时，局部纤维开始断裂，破坏区的树脂变为白色粉末，后部件破坏。
Fatigue process of FRP: the fatigue failure process of FRP is a comprehensive process of interface degumming, resin cracking and fiber fracture. For FRP laminates, the failure begins in the transverse fiber bundle perpendicular to the direction of alternating stress. The first is the degumming at individual points of the interface, which develops along the fiber direction, causing the transverse fiber bundle to peel off. After a period of time, there are cracks in the resin, and the parts gradually become opaque from translucency. When the cracks further expand, local fibers begin to break, the resin in the damaged area becomes white powder, and finally the parts are damaged.
影响玻璃钢疲劳强度的因素：玻璃钢是由无碱玻璃纤维布和合成树脂复合而成的材料，树脂种类不同时玻璃钢的疲劳强度也不同。对同类树脂来说，采用酚醛树脂或环氧树脂比采用聚酯树脂时的疲劳强度高。耐热型比普通型的疲劳强度高。若树脂强度相同，延伸率高的树脂其玻璃钢的疲劳强度也高。
Factors affecting the fatigue strength of FRP: FRP is a composite material composed of alkali free fiberglass cloth and synthetic resin. The fatigue strength of FRP varies with different resin types. For the same kind of resin, the fatigue strength of phenolic resin or epoxy resin is higher than that of polyester resin. The fatigue strength of heat resistant type is higher than that of common type. If the strength of resin is the same, the fatigue strength of FRP with high elongation is also high.
应力集中对玻璃钢的疲劳强度影响也较严重，在静态载荷作用下，玻璃钢比金属有较高的缺口敏感性，金属的应力集中系数为3,玻璃钢层压板的应力集中系数 为3~9。
The influence of stress concentration on the fatigue strength of FRP is also serious. Under the static load, FRP has higher notch sensitivity than metal. The stress concentration coefficient of metal is 3, and the stress concentration coefficient of FRP laminate is 3 ~ 9.