Friction materials have been traditionally associated with the auto industry as a means of transmitting power as well as retarding the speed of an automobile. The use of friction material has thus been limited to clutch and brakes. Advancements in these two areas, and also that of the friction linings has changed the way the brakes worked on the automobile in the 1940s compared to a vehicle in current times. While the development of friction brakes in motor vehicles began with the use of wood and leather as friction materials, the current requirements have to take into considerations like increasing legal restrictions regarding the use of raw materials. This not only calls for a new generation of friction materials, it also calls for the development of 'green materials'. Apart from being eco-friendly, friction materials also have to endure much abuse, and yet ensure safety without sacrificing on NVH. Irrespective of whether the friction materials are applied in clutch systems or brakes, they have to be far more robust than they were earlier. Engines develop more power and torque. Transmission systems and power management systems like centre differentials and mechatronic spin control systems have become more intelligent. This adds to the need for a material that much more advanced. Talk of advanced brake friction materials for instance, and brake friction material suppliers have spent significant R&D and financial resources over the past 25 years to develop advanced non-asbestos organic (NAO) brake friction technologies that optimise NVH performance and minimise brake dusting. A growing number of automakers, led by the Japanese OEMs, have recognised NAO ceramic friction brake pads as the best option for smooth, assured, quiet braking under a variety of driving conditions says an expert from the industry. He further adds that these news pads have helped OEMs to significantly reduce warranty costs by as much as 90 per cent. While next major advancements in NAO ceramic technology are expected to address high-temperature, severe-duty conditions, the stress is on sustainability and safety.Advancing transmission systems are leading to use of dry as well as wet clutches. Both use friction as a medium to transmit power. However, this gives birth to issues like vibration, energy losses and reliability. Auto components supplier Valeo offers G5 clutch facings in India, the first range of "green" clutch facings that enables considerable reduction in atmospheric emissions and improves working conditions. A France-based company, Valeo's most interesting recent contribution is probably the dual dry clutch, a key innovation representing a viable alternative to hydraulic automatic transmissions. With two clutches (one for even gears and one for odd gears), this system allows the driver to change gears with no interruption to torque and no jolting, just like an automatic transmission. Without a hydraulic circuit, it also improves efficiency, cutting consumption by 4-6%. Pointing at new technologies like the dry clutch, an analyst says that researchers and friction material producers are constantly analysing new types of metallic and composite friction materials and testing the components for wet- and dry-running applications. Simulation of customised test procedures is another typical activity. Interestingly, the manufacture and application of friction material based systems is not an easy task. Apart from friction materials, there is an amount of metallurgy involved. Then, there are the additives, and so on. The focus on brake NVH performance is a relatively recent trend. Until the 1980s, most motorists accepted a certain level of brake noise and roughness, even in some luxury and near-luxury models imported from Europe. The first breakthroughs in brake NVH technology coincided with the industry push to develop non-asbestos organic (NAO) brake pads. Much of this work was led by Japanese brake suppliers Akebono Corp., Nisshinbo (NBK) and Sumitomo. Their efforts focused on low metallic and other NAO friction formulations. Akebono introduced the automobile industry's first NAO brake pads for mass production featuring proprietary ceramic formulations in the 1980s. They were specifically engineered for the popular Honda Accord and Toyota Camry models sold in North America. These friction technology advances forever helped to change consumer expectations in North America and, not surprisingly, sales of these Japanese vehicles exploded. The Japanese OEMs set new performance and quality benchmarks for quiet, smooth braking that were admired by the entire industry. During this time, North American OEMs were losing long time customers to the Japanese automakers and facing a rising amount of costly brake noise warranty work. In response, the domestic auto industry began devoting increasingly more resources toward benchmarking Japanese vehicles to identify the attributes, which lead them to steady market gains in the early 1990s.Ford Motor Company led the charge during this time to make quiet, smooth braking the OE standard in North America. The best-selling Ford Taurus was one of the first North American passenger cars to feature ceramic brake pads. GM, concerned with brake noise on its growing line-up of light-duty trucks and SUVs, also began using ceramic friction products during the 1990s. DaimlerChysler began to focus more resources on brake NVH performance and advanced ceramic friction materials as well, particularly in North America.While NVH, and in other words acoustics, continues to assume greater importance, there is a growing demand for friction materials that last longer and endure more abuse. Especially when the levels of power transmission are rising, and systems like ESP, EBD, and regenerative braking systems demanding more out of friction materials.