在玻璃纤维船建造的早期,材料的耐用性和强度被低估了。建造者形成了厚实的船体,带有一体式管状肋和纵梁。玻璃纤维材料仍然很昂贵,随着对这些新船的需求增加,制造商开始削减成本以在市场上竞争。不久,添加了一层木材来减轻和加强船体和甲板。玻璃纤维和木质三明治是一个很好的组合,直到玻璃纤维的一个外表面被破坏。这被称为木芯构造。第一种类型的分层,其中木芯分离或分解,非常难以修复。需要移除其中一个玻璃纤维表面以进入核心。它通常是被去除的内部皮肤,因为它不太明显,所以完成质量并不重要。另一种类型的分层是类似的但没有木质层。在这些情况下,玻璃纤维本身的微小缺陷会使空气被截留。如果船体受到严重照顾,水可以通过微观通道进入并进入这些充满空气的空隙。这些微小水的膨胀和收缩将使空隙沿着玻璃纤维布和树脂粘合剂层水平生长。听起来很简单,但除非你有很多使用复合材料的经验,否则很容易使情况变得更糟。如果船要获得新的涂料涂层,颜色匹配的问题不是问题。将贴片混合到现有的涂料中是一种艺术形式,与浅色或深色涂料相比,浅色更容易匹配。由于这是计算机辅助设计工具之前的时间,美国西北部的建筑商使用旧的默认方法建造的更好。 1956年,当第一艘玻璃纤维船建造时,这种材料非常新,但已经在航空和汽车工业中得到认可。当时建造的唯一方法是使用浸渍丙烯酸树脂的玻璃纤维层,在固化时硬化。大型模具允许整个船体制成一体,没有接缝。船体内部增加了一些木结构以增加刚性,并用更多的玻璃纤维材料粘合在一起。如今所做的那样,没有采取预防措施来压缩固化船体或消除结构中的气泡。我们知道这种方法是坚实的核心结构。它没有在岩石上撞击让水进入木材层。小裂缝使木材变得浸透并膨胀,然后腐烂。不久,内外玻璃纤维层无法完成其工作,并因反复弯曲而失效。这是第一种类型的玻璃纤维分层,由于许多制造商已经过渡到所有玻璃纤维结构,留下了更多传统材料,因此失败严重损坏了造船业。由于分层问题,玻璃纤维结构很快被称为质量差。机械粘合是一个更大的问题,因为新的补丁仅通过粘合剂属性连接到船体。形成微小裂缝的相同振动将导致贴片的边界松动。一些水泡修复涉及钻几个非常小的孔并注入环氧化合物。然后压缩泡罩,同时环氧树脂固化。这使得补丁成为船体更加集成的部分。海洋生长可以穿透凝胶涂层并允许水进入结构区域。保持底部清洁并使用防污漆是最重要的一步。

加拿大曼尼托巴大学材料学Assignment代写:纤维玻璃分层

In the early days of fiberglass boat construction the durability and strength of the material was underestimated. Builders formed thick hulls with integrated tubular ribs and stringers. Fiberglass materials remained expensive, and as demand for these new boats increased, manufactures began cutting costs to compete in the marketplace. Soon a layer of wood was added to lighten and strengthen the hulls and decks. The fiberglass and wood sandwich was a great combination until one of the outer surfaces of the fiberglass was breached. This is called wood core construction. The first type of delamination, where a wood core either separates or disintegrates, is very difficult to repair. One of the fiberglass surfaces needs to be removed to access the core. It’s usually the inner skin that’s removed because it’s less visible so finish quality is not as important. Another type of delamination is similar but without the wooden layer. In these cases tiny flaws in the fiberglass itself allow air to be trapped. If the hull is cared for badly, water can enter through microscopic channels and enter these voids filled with air. Expansion and contraction of these tiny bits of water will make the voids grow horizontally along the layers of fiberglass cloth and resin binder. It sounds easy, but unless you have considerable experience working with composites it’s easy to make the situation worse. If the boat is going to get a new coat of paint the problem of color matching isn’t an issue. Blending a patch into existing paint is an art form and lighter colors are much easier to match than bright or dark paints. Since this was the time before computer aided design tools, builders in the North Western United States built using the old default method of more is better. In 1956, when the first fiberglass boat was built, the material was very new but already found acceptance in aviation and automotive industries The only way to build at that time used layers of fiberglass impregnated with acrylic resin that hardened when cured. Large molds allowed entire hulls to be made as one piece with no seams. Some wooden structure was added inside the hull for rigidity and it was bonded in with more fiberglass material. No precautions were taken to compress the curing hull or eliminate air bubbles in the structure as is done today. We know this method as solid core construction. It didn’t take a crash on the rocks to let water into the wood layer. Small cracks allowed the wood to become soaked and it swelled, and then rotted. Soon the inner and outer fiberglass layers couldn’t do their job and broke down from repeated flexing. This was the first type of fiberglass delamination and the failures damaged the boat building industry badly since many manufacturers had transitioned to all fiberglass construction, leaving more traditional materials behind. Fiberglass construction was quickly becoming known as poor quality because of delamination issues. Mechanical bonding is the larger issue since the new patch is only connected to the hull through adhesive properties. The same vibrations that formed tiny cracks will cause the boundary of the patch to loosen. Some blister repair involves drilling a few very small holes and injecting an epoxy compound. The blister is then compressed while the epoxy cures. This allows the patch to become a more integrated part of the hull. Marine growth can penetrate the gel coat and allow water into the structural area. Keeping a clean bottom and using an anti-fouling paint is the most important step.

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