Q: Do magnets with a larger diameter have more magnetic power?
If two magnets made from Neodymium have the same height dimension eg. 5mm, a wider diameter magnet will always have more magnetic power. Similarly, a thicker magnet with a larger height dimension will contain more volume and more magnetic material than a thinner magnet of the exact same diameter. In each case, the overall volume of magnetic material that lies between the two pole surfaces is what determines the comparative strength of the magnets. Altering the dimensions of a magnet can often solve issues around how to fit the magnet with the most suitable strength into confined or restricted spaces.
Other factors can also determine the strength of a magnet, including its N Grade and the type of magnetic material the magnet is made from. Neodymium N52 Grade magnets contain the highest concentration of rare earth material and therefore have a better maximum energy product than all other magnets with the same dimensions. N35 Grade is the lower end of the Neodymium grade scale in terms of holding power. Many applications do not require the highest grade Neodymium magnets to operate effectively and considerable financial savings can be made by using lower grade magnets. Higher concentrations of Neodymium in a magnet can also make the magnet a little more susceptible to cracking and impact damage.