Research Paper

An expository research paper on the production of fireworks

Fireworks

It's something we have all experienced. The lights, the shapes, the colors, and the sounds: they all amaze us. What am I talking about? It is something we take for granted but really is a complicated device created with much time and effort; that thing is a firework.

The first thing important to understanding how a firework works is to know about black powder. Black powder, also called gun powder, does not really, as most people think, cause an explosion, it simply burns very hot, creating a small explosion and lots of gas. In the open this would not do much, but in confined space enough pressure builds up to explode outward. Black powder was invented about 1,000 years ago in China, and consists of 75% saltpeter (potassium nitrate), 15 % charcoal, and 10% sulfur. The speed at which it burns can be controlled in many ways. One of the simplest is to change the size of the grains because finer grains burn faster.

The next important component of a firework is a group of stars. Stars are the things that cause the bright colors and flashes that we see. An unlit star, however, just looks like a little black lump the size of a gumball. Stars are made of black powder, perchlorate (salts of HClO4, used as a propelling agent), bonding agents and coloring agents. These coloring agents include Magnesium or Aluminum to create white, sodium salts to create yellow, strontium nitrate or carbonate to create red, barium nitrate to make green, copper salts for blue, and some form of carbon to create orange. These ingredients are mixed to form a big slab of dough which is cut apart, shaped into spheres, cylinders, or cubes, and left to dry.

These stars are packed into a spherical or cylindrical shell with a center of black powder and a time delay fuse. This shell is connected to a cylindrical base which contains a main fuse and enough black powder to get the shell in the air; all of which is stuffed into a very snug tube. The main fuse is an electrical wire with one end attached to two secondary fuses and the other end attached to a main control program. A computer program or operator ignites the fuse, sending an electric current through it which creates a spark which, in turn, ignites the two secondary fuses. One fuse ignites the time delay fuse in the shell while the other one ignites the black powder at the bottom called the “lift charge.” The lift charge quickly builds up a lot of pressure in the launch tube, or “mortar” which projects the firework into the air. Meanwhile, the time delay fuse continues to burn and ignites the black powder, which ignites the stars and blasts them outward exactly at the apex of the firework's flight.

The firework I described above is a rather simple one. Most fireworks today contain compartmentalized stars with several groups which ignite separately creating multiple dazzling explosions. Another design involves several small shells packed into a larger shell so that they explode apart each exploding separately creating an amazing cascading effect. The most common of today's designs, however, is the multi-break firework. It consists of several segments which are separated by break charges, each break charge igniting the fuse of the next break. This allows one to have multiple colors and explosions in one firework. Break charges also have chemicals or devices added to them so they make whistles or loud booms.

Fireworks are incredible spectacles to behold. They are complex; they are beautiful; and they are amazing. Next time you see a fireworks show, think of how much work went into making it. It will make it all the more spectacular.