Disc brakes are frequently used in modern vehicles. Brake rotors that turn with the wheels are attached to the wheels. When the brakes are engaged, brake calipers compress the brake rotors. In order to lessen the amount of friction caused by metal on metal, a brake pad is placed between the rotor and the caliper. The pads need to be replaced over time. If the brakes are applied suddenly, the car may pull up to a stop sign or make a screeching noise. These are signs that the pads need to be replaced.
In disc brakes, each disc rotor typically has two brake pads that function together. A caliper attached to the wheel hub or suspension upright holds them in place and controls their movement. However, for the best performance, racing calipers might use up to six different types of pads with different frictional properties arranged in a staggered pattern.
Thus, in this article, I’ll be discussing the meaning, functions, types, and workings of a brake pad. You’ll also know how often you should change your brake pads and factors that affect how long your brake lasts.
Ok, let’s dive in!
What is a brake pad?
The majority of cars used a wooden block as its brake until the 1890s. The vehicle came to a stop when the driver depressed a lever, which in turn caused the block to scrape against the wheels. The wooden block stopped being the most effective braking technique once cars started moving faster (over 10–20 mph) and wheels became more sophisticated. The first remedy was created in 1898 by inventor Elmer Ambrose Sperry: a car with front-wheel disc brakes and brake pads that “pinched” the rotor or disc, operating similarly to bicycle brakes.
The brake pad is a thin block that presses against the disc in a disc brake, typically one of a pair. In automobiles and other applications, brake pads are a component of disc brakes. Steel backing plates make up brake pads, and friction material is adhered to the surface facing the disc brake rotors. Each wheel’s brake caliper, brake disc, and brake pads make up the usual vehicle braking system.
The caliper is designed to hold the pads, which have their friction material virtually touching the brake disc’s two sides. Hydraulic fluid in the caliper pushes each brake pad on either side of the rotating brake disc when the brake pedal is depressed. The friction that arises from this causes the car to slow down and eventually stop.
Functions of the brake pad
By friction, brake pads convert a vehicle’s kinetic energy into thermal energy. In the brake, two brake pads are positioned with their friction surfaces directed toward the rotor. The hydraulic caliper compresses or squeezes the two brake pads against the rotating rotor to slow down and stop the car when the brakes are engaged.
A dull gray coating is left on the disc as a result of the friction material from the brake pad being transferred onto the disc in small amounts as it heats up in contact with the rotor. Due to the application of friction material to both the brake pad and disc, friction is created between them that stops the car.
Types of brake pads
Here are the most common types of brake pads:
Non-metallic brake pads are the softest type of brake pad available. They are produced and cured to withstand a significant amount of heat and are composed of various combinations of glasses, rubbers, and resins like cellulose as well as a sparse amount of metal ﬁbres.
The resulting composite is soft and quickly degrades, yet it is kind on brake discs. They are therefore inadequate for use in any situation other than daily road driving, and even then, a more metal-based pad is recommended to prevent needing to replace them frequently.
The majority of the cars sold nowadays come with these types of brake pads. To create a hybrid compound that is primarily made of metals, they combine synthetic materials and metals. Once the fibers’ composition has been determined, an organic resin is used to bind them together. To increase their durability, they are then molded into certain forms and baked for three to five hours in a furnace.
However, because metal has a lower friction coefficient at low temperatures than the more malleable synthetic material, slightly more pedal force is required to produce the same braking force with the semi-metallic pads when cold. This is because metal has a lower thermal conductivity than the purely organic variants.
But, if brake fade still occurs with a set of steel brake pads as a result of overheating, then investing in a set of full ceramic brake pads would be worthwhile. The ceramic compound employed in these high-spec pads, which are only available for the priciest supercars because of the sheer cost of production, is incredibly effective at absorbing heat from very hard, continuous, violent braking.
This means that they can continuously recover from any demands made on them, including those in activities like endurance racing. However, because of this characteristic, ceramics can be challenging to warm up to operating temperature, which can be problematic for daily driving.
How do modern brake pads work?
Simply explained, the friction created by contact between your brake pads and rotors slows and stops your car. Brake pads are a part of a complex system that depends on each of its components to operate securely and effectively. Your brake pads’ role is as follows:
- When you press the brake pedal, a cylinder opens, sending brake fluid down the pipes to the calipers.
- Your brake pads are engaged by the calipers.
- The rotor, which is directly attached to each wheel, is subjected to pressure from your brake pads.
- The friction produced by this pressure is what allows your car to slow down or stop. Your wheels slow down along with the rotor.
- The brake pads loosen, fluid flows back up the hoses, and your wheels resume motion when you lift your foot off the brake pedal.
Watch the video below to learn the workings of a brake pad:
What factors can affect how long your brake pads last?
To know how long your brake pads might last, it’s important to consider the following factors:
Where you drive
Your brake pads may last longer if you conduct most of your driving on highways than if you travel more in inner cities and on shorter trips. Because driving through cities sometimes necessitates stopping and starting at traffic lights, roundabouts, and junctions, your brakes are required far more frequently than they are when driving down a highway.
How many miles do you cover?
Although it varies depending on the sort of road you’re on, you use your brakes more frequently and your brake pads wear down more quickly the more miles you log. That’s all there is to it. Because the front brakes bear more of the braking load, they often deteriorate more quickly than the rear brakes.
Type of brake pads
The durability of the different types of pads you can have in your car varies as well:
- The cheapest brake pads are often made of organic materials, however, they last less time. Low metallic brake pads can be noisy, but they last a little bit longer than organic brake pads.
- Sintered or semi-metallic brake pads combine various materials with fused metal particles, like copper and bronze. Although they have a long lifespan and provide good braking performance, they may cause brake discs to wear out more quickly than other pads.
- Ceramic brake pads are more durable and have a longer lifespan than other materials. The disadvantage is that these also cost more than other options.
The weight of the car
The weight that is routinely carried by the vehicle, such as four or five passengers, a completely loaded trunk, pulling a caravan, etc., is another influence on brake pad wear. It is simpler to slow down and stop with less braking force when the vehicle is lightweight.
A vehicle carrying a 5-person family will obviously weigh more than one carrying, say, a couple. As a result, stopping it in the same period of time will need more force and place a larger strain on the brake pads.
What Else Is Checked During A Brake Job?
The brake rotors’ thickness is tested, and any evidence of scoring, abrasion, or uneven wear is examined. For damage, scuffs, and other flaws, the brake disc is examined. There is a check on the reservoir’s braking fluid level.
the car’s suspension system will likely get a fast once-over from the mechanic, along with checks for leaks below the car and the condition of the brake lines. While they have the chance, they could also examine the state of your wheel bearings and steering system as these are simpler to access while a wheel is off.
It’s simple to physically inspect the condition of your car’s braking system, and mechanics won’t replace a part unless it’s almost worn out. Just ask the technician to show you the replacement parts and their level of wear. They will be delighted to demonstrate the damaged components and discuss why replacement was necessary.
- Brake pad and rotor replacement cost
- Squeaking Noise While Driving But Not Brakes Applied (what to do)
- What is the ideal brake pad thickness and how to check it
- Brake pads change: how often & signs that it’s time
- Ceramic vs. Organic Brake Pads: Advantages, Disadvantages, and Differences
- Understanding Hydraulic Braking System
- The most common and possible causes of brake noise
In conclusion, brake pads are essential parts of a car’s braking system and play a crucial part in providing reliable stopping power. Their importance comes from their capacity to transform kinetic energy into thermal energy, which eventually causes the vehicle to stop.
These small yet essential components are made of a variety of materials, such as organic, semi-metallic, and ceramic, each with certain benefits and characteristics. When brake pads press on brake rotors, friction is created, which slows down and stops the vehicle.
Vehicle owners must be aware of the meaning, functions, types, and workings of brake pads. Maintaining optimal braking performance and guaranteeing road safety requires regular inspections, maintenance, and the prompt replacement of worn brake pads. Brake pads are a prime example of how seemingly unimportant parts have a significant impact on a vehicle’s overall functionality and safety.
That is all for this article, where brake pads are discussed. I hope it was helpful, if so, kindly share it with others. Thanks for reading, see you around!