환원철을 이용한 브레이크 패드의 성능에 관한 연구(철 혼합비의 영향을 중심으로 본 마찰재의 성능 변화)

남현우,이효림,김병삼 한국기계기술학회 2022 한국기계기술학회지 Vol.24 No.2

Various kinds of friction materials were manufactured by adding 10%, 20%, and 30% of reduced iron, respectively, which has been obtained during the reduction process of blast furnace sludge extracted from the blast furnace, and its iron oxide, instead of existing barium sulfate(BaSO4) among the components of automobile brake friction materials. Fundamental physical property test and friction performance test, etc., using a brake dynamometer were carried out against these friction materials. Furthermore, when the expensive filling material, BaSO4 was substituted by reduced iron and added to the friction material, the added content of reduced iron for an excellent friction characteristic considering the heat emission temperature, wear, etc., was 10%. In the fundamental physical property test, as the added content of blast furnace sludge or reduced iron increased, and as the content increased, the shear strength and bonding strength of friction materials decreased, but both of them indicated sufficient strengths to be applied to a friction material. Even in the frictional performance test using a brake dynamometer, as the added content of blast furnace sludge or reduced iron increased, the friction coefficient reacted insensibly to brake deceleration, and its stability was improved.

Tribological Properties of Brake Friction Materials with Steel Fibers

박성빈,조근형,Sola Jung,장호겸 대한금속·재료학회 2009 METALS AND MATERIALS International Vol.15 No.1

The tribological properties of brake friction materials with and without steel fibers were investigated. The focus of this study was determining the effect of steel fibers on the speed sensitivity of the friction coefficient. The speed sensitivity of the friction coefficient is closely associated with the stick-slip phenomenon. The results indicate that the friction material containing steel filbers was more sensitive to sliding speed, exhibiting a highly negative μ-v relation. In particular, the friction material with steel fibers showed a larger vibration amplitude during brake applications, suggesting that the μ-v relation was strongly related to the friction-induced vibration. On the other hand, the wear resistance of the friction materials containing steel was significantly better than that without steel fibers, suggesting longer service life. A possible mechanism of the stick-slip by the steel fibers is discussed in terms of the physical properties of the steel fiber and the gray iron rotor. The tribological properties of brake friction materials with and without steel fibers were investigated. The focus of this study was determining the effect of steel fibers on the speed sensitivity of the friction coefficient. The speed sensitivity of the friction coefficient is closely associated with the stick-slip phenomenon. The results indicate that the friction material containing steel filbers was more sensitive to sliding speed, exhibiting a highly negative μ-v relation. In particular, the friction material with steel fibers showed a larger vibration amplitude during brake applications, suggesting that the μ-v relation was strongly related to the friction-induced vibration. On the other hand, the wear resistance of the friction materials containing steel was significantly better than that without steel fibers, suggesting longer service life. A possible mechanism of the stick-slip by the steel fibers is discussed in terms of the physical properties of the steel fiber and the gray iron rotor.

친환경 법규 대응을 위한 복합재 브레이크의 Cu Free 마찰재 개발에 관한 연구

심재훈,이중희,신웅희,임동원,현은재 사단법인 한국자동차안전학회 2022 자동차안전학회지 Vol.14 No.2

Composite material is widely used in the automotive industries because it has excellent mechanical properties and is possible to reduce weight due to the low density. However, there is a new obstacle to meet environment regulation like Cu less or Cu free regulation for the friction material. Although it is strongly demanded, there are few research results about that unfortunately. Unless this problem is not solved properly, it is impossible to apply composite brake system to vehicle. In this paper, a new eco-friendly friction material for composite brake system is represented to respond these regulations. To do this, friction characteristics between existing low steel friction material and new eco-friendly friction material are verified to secure performances for brake system such as effect characteristic, fade characteristic and wear characteristic. And composite brake gets the equivalent or better performance compared to a low steel friction material. Finally, this result contributes to the study of major principles for the development of eco-friendly friction material in the future.

Characteristics of Graphite Particle Size comprised in Metallic Friction Material

Kim, Young Gyu,Lee, Jong Seong,Kim, Sang Ho,Lee, Hi Sung The Korean Society for Railway 2012 International Journal of Railway Vol.5 No.4

The essential element of brake device for railway vehicle is in demand for higher performance along side the trend of railway vehicle size and speed. Essential element of brake device for high speed train is composed of metallic friction material and brake disc. Thus, brake distance, duration and brake stability shall be determined due to friction materials and friction characteristics. Also friction characteristics are influenced by metallic friction material's properties of matter, manufacturing process and component parts. Various materials and configurations of metallic friction materials are currently being implemented to railway vehicles, For this reason study of friction characteristics in accordance with materials is necessary, but study of these important elements are not actively being accomplished. Therefore, in this study, wished to study the graphite's friction characteristic comprised in friction material in accordance with particle size and amount of volume through lab-scale test.

자동차용 브레이크 마찰재에서의 환원분철의 마찰특성에 관한 연구

정진오,이경환,김옥삼,김봉수 순천대학교 2000 순천대학교 자연과학논문집 Vol.19 No.1

In most automotive brakes, the friction material is used to convert the kinetic energy into heat. The friction material is a complex composite consisting of a resin, reinforcing fibers, lubricants and filler materials. In an attempt to enhance the friction performance of the friction material, a trial was done to examine the substitution of filler material by the reduction iron powder. In this study, two types of reduction powder M1 and M3 was prepared by the reduction process developed by Hanta M&B Inc. M1 and M3 which has reduction ratio of 1.5 and 92% respectively was used in place of BaSO_4, which was conventionally used as a filler material. The amount of M1 and M3 was varied as 10, 20, 30%, while the other component remains the same except the replaced BaSO_4. For those specimens with different amount of reduction iron powder, friction performance tests such as friction coefficient, rotor compatibility were conducted by using brake dynamometer. The bonding strength and hardness tend to decrease with use of M1 and M3, but specific weight decreased with increase of M1 and M3. The friction coefficient increased with use of M1 up to 10%, but decreased for use of M1 more than 20%. However the use of M3 resulted in a decrease of friction coefficient all the way. The surface roughness decreased with the use of M1 and M3, except for a case of excessive use of M1 of 30%. The rotor surface roughness did not show any correspondence with hardness of friction material in this study.

Characteristics of Graphite Particle Size comprised in Metallic Friction Material

Young Gyu Kim,Jong Seong Lee,Sang Ho Kim,Hi Sung Lee 한국철도학회 2012 International Journal of Railway Vol.5 No.4

Friction Characteristics of Non-Asbestos Organic (NAO) and Low-Steel Friction Materials: The Comparative Study

Kim, Seoun Jin,Jang, Ho Korean Tribology Society 2000 KSTLE International Journal Vol.1 No.1

Eviction characteristics of two typical friction materials (non-asbestos organic and low-steel friction materials) for an automotive brake system were investigated using an inertial brake dynamometer. In particular, the effect of sliding speed on friction coefficient was carefully investigated employing various test modes. The two friction materials were developed for commercial applications and were different mainly in the type and the amount of metallic ingredients in the friction material. The dynamometer test showed that the low-steel friction material was sensitive to the sliding speed exhibiting a negative $\mu$-v relation. On the other hand, the non-asbestos organic friction material was less sensitive to the sliding speed. The low steel friction materials with a negative $\mu$-v relation also induced larger vibration amplitude during brake applications.

환원분철을 이용한 자동차 브레이크용 패드 개발

김병삼 ( Kim Byoung-sam ),정영달 ( Chung Young-dall ),이성기 ( Lee Sung-ki ) 한국환경기술학회 2000 한국환경기술학회지 Vol.1 No.3

Friction material is a very important element of disk brakes, because it is directly related to brake performance in such areas as effectiveness, friction stability with various brake conditions, pad life and different kinds of noise and vibration. Although friction material manufactures have worked to develop many different friction materials, very few studies have been published about the development of friction materials. Therefore knowledge of friction material development is not widespread. The scope of this paper is the basic considerations, studies and experiments which focus on brake pad development using sponge iron of blast furnace waste.

Green composite friction materials: A review of a new generation of eco-friendly brake materials for sustainability

Amira Sellami,Riadh Elleuch 대한환경공학회 2023 Environmental Engineering Research Vol.29 No.3

Particulate matter (PM) still poses a significant threat leading to air pollution which is responsible for continued damage to human health and the environment. Particulate matter resulting from non-exhaust emissions are considered as viable a source comes mostly from brake pad wear concept. The scientific challenge of this work is to stimulate a new generation of green friction materials to reduce particle emissions having low-environmental impact. The specificity of braking materials, their effects on the environment and human health are studied. To minimize the levels of air pollution, the use of green friction composites collected from natural elements reducing human diseases is discussed. For this purpose, the novel and high-performance friction composite materials synthesized from vegetable and animal waste used as a raw material are reported. The natural powder and fiber treatments, the optimum formulation and the binder materials related to the green friction composites are reviewed. An overview of environmentally ecofriendly green friction materials embedded by reinforcing phases of natural elements exhibiting excellent mechanical and tribological properties are mentioned. Therefore, scientific and industrial efforts should concentrate on the development of green friction materials to minimize the effect of transport related air pollution.

환원분철을 이용한 마찰재의 성능에 관한 연구

김병삼(Kim, Byeong-Sam),문상돈(Moon, Sang-Don),지창헌(Chi, Chang-Heon) 한국산학기술학회 2008 한국산학기술학회논문지 Vol.9 No.3

브레이크 마찰재의 구성성분 중 기존에 시용되던 무기 충전재인 BaSO₄ 대신에 고로슬러지와 그 산화철에 일련의 환원과정을 행하여 얻은 환원분철을 10%, 20%, 30%씩 첨가하면서 몇 종류의 마찰재를 제작하였다. 이 마찰재들에 대해 기본 물성시험, 브레이크 다이마모미터를 사용한 마찰성능 시험 등을 행하였다. 그리고 고가의 충전재인 BaSO₄를 환원분철로 대체하여 마찰재에 첨가한 경우, 발열온도, 마모 등의 마찰특성이 우수한 환원분철의 첨가량은 10%이었다. 고로슬러지나 환원분철 시편에서 고로슬러지와 환원분철의 첨가량이 증가할수록 마찰재의 전단강도와 접착강도는 감소하나 모두 마찰재로서의 적용에는 충분한 강도를 나타내었다. It was made a friction material of various kinds by adding 10%, 20% and 30% of reduced iron. It was obtained by a connected-reduced process in a blast furnace sludge and oxidized iron, instead of BaSO₄, which is already a used inorganic filling material among a component of a brake friction material. This was done by a basic physical property test, a friction performance test to use a brake dynamometer. Moreover, in case of an add in the friction material, instead of using BaSO₄, the more expensive filling material, the reduced iron was also better because it has an excellent a friction property of an exothermic temperature, wear, etc. was 10%. At Gland G3 specimens, a shear strength and a bonding strength of the friction material was decreased to be able to increase an amount of the blast furnace sludge and the reduced iron, but an application of all friction materials appeared enough strength.