快速了解常见而特殊的材料——耐火砖

耐火砖是什么，有什么用？
What Are Refractory Bricks and What Are They For?
由专筑网邢子，小R编译
从黄色到灰色，再到传统的红色和橙色，砖在许多城市中无处不在，并广泛用于建筑工程。简而言之，传统砖的制造过程包括将粘土成型，并在炉子里烧制，制作实心砖、穿孔砖、科博哥砖、瓷砖和其他形式的砖。陶瓷砖便宜易得，具有很强的抗性、热惯性和表面处理能力，而且不需要专业的施工能力。但如果将这种砖放置在高热源附近，最终会出现开裂、断裂的情况，相比之下，耐火砖更加适合，这意味着什么呢？
Ranging from yellow, to gray, to traditional red and orange, bricks are ubiquitous in many of our cities and widely used in construction. Briefly, the manufacturing process of traditional bricks involves molding clay and firing it in ovens, facilitating the creation of solid blocks, perforated blocks, cobogós, tiles, and other shapes. Ceramic bricks are inexpensive; easy to find; boast strong resistance, thermal inertia, and finish; and do not require such specialized labor for construction. But if the installation is done near sources of high heat, the common brick will end up cracking and breaking, making refractory bricks more suitable. But what does that mean?

Andrey Solovev (shutterstock)
看似矛盾的是，在1000℃以上的烤箱中烧过的材料不能承受高温，其实，主要问题是热冲击。当普通砖与热源接触时，会迅速膨胀，当热源停止时（比如火熄灭），材料就会收缩。这些温度的突然变化会影响结构的稳定性，会形成裂缝等严重问题。耐火材料是指那些能够承受高温而不被高温破坏其结构、电阻或导热性的材料。就砖材料而言，耐火砖的化学成分与普通砖不同，这会影响其颜色和导热系数。
It may seem contradictory that a material that has been burned in ovens at temperatures of more than 1000° C cannot withstand high temperatures. In fact, the main problem is thermal shock. When the common brick comes into contact with a heat source, it expands quickly. When the source ceases (the fire extinguishes, for example), the material contracts. These sudden changes in temperature affect the stability of the structure and can form cracks and other serious problems. Refractory materials are those that can withstand high temperatures without the heat damaging their structure, resistance, or thermal conductivity. In the case of bricks, the chemical composition of refractories is different from that of regular bricks, which also influences their color and thermal conductivity.

photowind (shutterstock)

baxys (shutterstock)
对于家庭用途，如烤箱、烧烤炉和壁炉，使用的耐火砖通常由粘土组成，主要含有氧化铝和二氧化硅，这些元素能够承受高温。氧化铝具有反射性，而二氧化硅则是一种优良的绝缘体。混合物中存在的氧化铝越多，砖所能承受的温度就越高（这是工业用途的重要考虑因素），砖的价格也就越高。硅石的颜色比较灰暗，而氧化铝的外观比较黄。
For domestic uses, such as ovens, barbecue grills and fireplaces, the refractory bricks used are usually composed of clay containing mainly alumina and silica, elements capable of withstanding high temperatures. While alumina has reflective qualities, silica is an excellent insulator. The more alumina present in the mixture, the higher the temperature that the brick will endure (an essential consideration for industrial uses) and the more expensive the piece will be. Silica has a more grayish tint, while alumina has a more yellowish appearance.

AntoshchukLana (shutterstock)
除了技术功能外，还有建筑师使用外露的耐火砖来建造和装饰表面。在设计工作小组开发的“热带之家Urveel”项目中，耐火砖有多种使用方式，有时呈现出像“Indian jali”一样的多孔形式，有时不透明且有纹理，有时形成天井，有时作为背景，这些砖可以应用在整个房子里。
In addition to the technical function, there are architects who use exposed refractory bricks to build and coat surfaces. In the Tropical House Urveel project, developed by Design Work Group, refractory bricks were used in several ways. Sometimes porous like an "Indian jali," sometimes opaque and textured, sometimes forming a patio and sometimes acting as a background, these bricks were seen throughout the house.

Tropical House Urveel / Design Work Group. Image © Photographix

Oleksandr Rostunov (shutterstock)
除了砖本身，所使用的砂浆也必须能承受高温。因此，它通常由特殊的骨料组成，如蛭石和耐火粘土，和砖一样，它也可以含有氧化铝（Al2O3）、莫来石-锆石等材料。
始终要强调的是，在设计或建造将与热源接触的结构时，必须注意所使用的材料与当地的规定一致。为了避免材料损失或更严重的事故，设计前期需要付出一点时间与精力，例如积极寻求专家和制造商的建议。