| 摘要 |
PURPOSE:To reduce a brake noise without impairing the brake characteristics, by limiting the quality of material used for a liner. CONSTITUTION:In time of manufacturing a brake drum 1, the quality of material for a liner 2 to be internally chilled in molten aluminum is formed of pearlite cast iron on which flake graphite is distributed to a pearlite base in an area ratio of more than 90% and set down to carbon equivalent (C+Si/3): 4.3-4.8wt%, a precipitate carbide: below 5wt%. In this connection, the form of the flake graphite distributed to the pearlite base is recommended to a C type as a desirable one. The carbide acts so favorable in reducing wear in the liner but since it causes a drop in damping capacity on the other side, the amount of precipitation is set to below 5% or it is preferable not to be precipitated otherwise. For your information, as an alloy element, it is allowable to contain a minimal amount of Cr, Cu and Ni. |
