江蘇春晨電纜有限公司生產(chǎn)YFFBPGG扁電纜 春晨3*120，YFFBPGG扁電纜 春晨3*120，

如45號鋼經(jīng)亞火處理后疲勞極限為34.3MPa，經(jīng)退火處理后為24.5MPa。經(jīng)840℃淬火，420℃回火處理后為52.9MPa。由此可見45號鋼經(jīng)不同熱處理后其機(jī)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.

環(huán)氧酚醛玻璃鋼的疲勞特性：玻璃鋼是一種多相材料，是一種纖維重合材料，是一種脆性材料（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%)

玻璃鋼的疲勞過程：玻璃鋼的疲勞破壞過程是界面脫膠、樹脂開裂和纖維斷裂的綜合過程。對于玻璃鋼壓板來說，破壞開始于與交變應(yīng)力方向垂直的橫向纖維束內(nèi)，首先是界面?zhèn)€別點(diǎn)處的脫膠，脫膠沿著纖維方向發(fā)展，致使橫向纖維束產(chǎn)生剝離。經(jīng)過一段時間，樹脂內(nèi)產(chǎn)生裂紋，部件由半透明逐漸變?yōu)椴煌该鳎?dāng)裂紋進(jìn)一步擴(kuò)大時，局部纖維開始斷裂，破壞區(qū)的樹脂變?yōu)榘咨勰蟛考茐摹?/p>

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.

影響玻璃鋼疲勞強(qiáng)度的因素：玻璃鋼是由無堿玻璃纖維布和合成樹脂復(fù)合而成的材料，樹脂種類不同時玻璃鋼的疲勞強(qiáng)度也不同。對同類樹脂來說，采用酚醛樹脂或環(huán)氧樹脂比采用聚酯樹脂時的疲勞強(qiáng)度高。耐熱型比普通型的疲勞強(qiáng)度高。若樹脂強(qiáng)度相同，延伸率高的樹脂其玻璃鋼的疲勞強(qiáng)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.

應(yīng)力集中對玻璃鋼的疲勞強(qiáng)度影響也較嚴(yán)重，在靜態(tài)載荷作用下，玻璃鋼比金屬有較高的缺口敏感性，金屬的應(yīng)力集中系數(shù)為3,玻璃鋼層壓板的應(yīng)力集中系數(shù) 為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.