Railway brake pads are primarily categorized into composite (organic), sintered metal, and cast iron. For high-speed passenger trains, sintered metal pads are preferred due to their excellent thermal conductivity and stable friction coefficient at high temperatures. For freight or heavy-haul railways, high-friction composite pads are often used to reduce noise and wheel wear. You must select the material based on the axle load, maximum speed, and braking system pressure of your specific rolling stock.