Basalt fiber occupies more and more niches in application due to its properties, displacing somewhere less durable fiberglass, somewhere more expensive carbon fiber. High abrasion resistance, low weight, excellent mechanical strength, high resistance to acids, alkalis and salt solutions, magnetic and electrical inertness, and many more remarkable qualities, along with the wide distribution of raw materials for production, makes basalt fiber a really interesting material for a number of applications.





Basalt



The most common rock in the crust is basalt. At its core, it is magma spilled from the vents of volcanoes in molten form. Having entered into interaction with the atmosphere, it somewhat changes its properties, spreading in lava flows, and gradually cools down. Basalt deposits are in almost all countries, their reserves are huge.Basalt has been used as stone by mankind for a long time, but the idea to produce fiber from it came to the Frenchman Paul De, who received a patent for his invention in 1923 in the United States. The invention did not cause much excitement at that time, and the Cold War period in the 60s of the last century became a catalyst for active development in this area. Under the label of secrecy, the USA and the USSR began to investigate the properties and possibilities of using basalt fibers. First of all, of course, in military applications. The USSR Development Center was based in Kiev, where in the 80s an industrial method for the production of basalt fiber was developed. Nevertheless, the imperfection of the technology of that time slowed down the research practically all over the world and forced to return to the old proven methods of using fiberglass. Later, carbon fiber will enter the arena, which is very expensive in production due to a whole cycle of treatments, but with useful characteristics for the military-industrial complex, which became the main impetus for its application.





Production process
The production of basalt fiber takes place in one step: by melting the crushed basalt in a melting furnace at a temperature of 1500 ºС, followed by flowing out through plates with funnel-shaped openings (dies). Depending on the modification of the fiber, it can be staple or continuous. To obtain fine fibers, the melt flowing from the spinnerets is blown up with a stream of compressed air, less often another method is used - they are sprayed with centrifugal devices. Continuous fiber is obtained by drawing the solidifying melt from the spinnerets into filaments and winding them onto spools. Thin fibers are deposited in the form of individual superthin villi continuous fiber is a thread. Fiberglass is made by a similar technology, but from several components, for basalt fiber, nature itself took care of the preparation of the raw material and its homogenization. No chemical additives - nothing but natural non-metallic, inorganic raw materials.
Basalt fiber in composite materialsHigh indicators of basalt fiber resistance to aggressive environments, high temperature and ultraviolet, incombustibility and electromagnetic inertness open up wide opportunities for its use in various composite materials. Composite is a product of several components: matrix (or binder) and filler. As a filler, both the actual fibers (fibrous composites) or basalt scales, as well as rovings, cords, fabrics, canvases or tapes obtained from continuous fiber (layered composites) are used. By virtue of its characteristics, basalt fiber can serve as a filler for a wide range of matrices: metal, polymer, wood, ceramic, concrete, gypsum and asphalt. By varying the material of the binder and filler, products with the most suitable properties for a particular application are obtained. Thermoplastics-based basalt composites have excellent crack resistance, impact strength and are easy to process under high temperatures. The process of producing composites with a thermosetting matrix is ​​longer than for thermoplastic ones due to the longer process of molding and hardening the matrix. Therefore, the leading manufacturers of vehicles (cars, ships, aircraft) focused on the development and improvement of thermoplastics in order to obtain products with parameters on an industrial scale that are not inferior to thermoset composites. For heat-resistant basalt composites, ceramic and metal are used as the matrix material. The main application of such materials is rocket and aerospace industries. For example, the California State Polytechnic University in Pomona (USA) is actively working on the development of advanced fiber-reinforced composites with an aluminum matrix, the National Technology Center for Metals and Materials in Thailand published successful results on the use of basalt fiber as a filler for a ceramic composition, and NASA also in 2011, it patented a ceramic-basalt composite for rocket engines (US patent 7,968,620 B2). The most widespread at the moment basalt products are in the construction industry. Concrete reinforced with basalt fiber demonstrates higher crack resistance, bending and tensile strengths. But concrete is walls, and ceilings, and bridge structures, and underground utilities, including arched. Basalt fiber perfectly tolerates the increased humidity of hydraulic structures, as well as cyclical seasonal temperature changes, the effect of aggressive chemical media and saline solutions. Reinforcement and masonry mesh made of basalt fiber are already successfully used at construction sites, increasing not only the speed and quality of work, but also the durability of the object. The pavers use composite fabrics of basalt fiber, geogrids and geogrids, strengthening the ground or for bonding with subsequent layers of pavement on the tracks. Mineral wool made of thin basalt fibers has also proved to be excellent - it is an excellent thermal and sound insulation, which has found application both in housing construction and in industrial construction. In addition, high-quality filters for chemical and pharmacological laboratories are produced from non-woven basalt materials. Active development of tanks and cylinders of continuous basalt fiber, which promise to become ideal containers for storage and transportation of chemical liquids. The head of the company Infinite Composites Technologies, which produces cryogenic cylinders (for liquefied fuels at low temperatures), said that potential buyers showed great interest in their first samples, which they are currently improving.Focus on the environmentBasalt fiber: from the vent of the volcano to modern composites Source: NICHE The main trends of modern industry are energy efficiency and environmental protection. Recent developments and studies of the world's leading laboratories are aimed at minimizing greenhouse gas emissions and the creation of closed-loop industries. Basalt fiber is considered by a number of projects as one of the most advanced materials in this direction: its production is characterized by low energy consumption, waste from the manufacture of composites can be used to obtain other products, and basalt composites themselves can be easily recycled. The innovative company Niche, for example, already a few years ago created a completely recyclable snowboard with basalt fiber. The European Union has now launched a number of projects for the widespread introduction of composites in shipbuilding: RAMSSES, FIBRESHIP. Shipbuilders pay serious attention, including to basalt composites, for this there are a number of reasons. The main ones are the resistance of basalt fiber to corrosion, incombustibility, strength and low weight. In 2018, as part of the leading world composite show JEC World, the basalt fiber eco-yacht project of the Italian company GS4C srl was nominated for the JEC Innovation Award in the Sustainability section, which is a significant assessment of the team's efforts. GS4C (“Go Sailing, for a Change”) successfully implements sustainable solutions in line with world trends, working on processes and materials for building composite boats with the possibility of their processing at the end of the life cycle. The company has already patented the technology for producing fiber-metal laminate (Fiber Metal Laminate) - a composite of thin layers of aluminum and basalt fiber connected by vacuum infusion. The global auto industry is also interested in researching new materials that extend the life of cars, reduce their weight and, consequently, fuel consumption. Thanks to such technologies, liquid fuel vehicles will reduce emissions, electric vehicles will increase the range without recharging. Not only brake pads, thermal insulation on exhaust pipes and other technical details are made of basalt fiber. From a basalt composite, LARTE Design tuning studio created cutting-edge tuning kits for Tesla electric cars, premium Infiniti SUVs and other prestigious cars. The Roller Team, which developed the Trigano Group Triaca Concept 230 camping car, put on its basalt body. Basalt raw materials and fiber began to be used in additive industries, where waste is practically eliminated, and this opens up new horizons for its application.