Sodium and Potassium metals are the two metals which are soft and can be cut with a knife.
Sodium belongs to alkali group metal(first group of the periodic table) and it can easily be cut with a knife. As the atomic size increases down the group, the force of attraction between the valance electron and nucleus decreases. Metallic bonds are not strong. Sodium is very soft.
Metals like sodium and potassium are very hard and cannot be cut knife easily.
The two most common nonferrous metals DIYers need to cut are aluminum and copper. Nonferrous metals are usually softer and easier to cut than ferrous metals.
Zinc sheet metal can be cut with a variety of different tools. A sharp knife or pair of scissors can be used to score the metal and then snap it along the scored line. A power saw can also be used, but it is important to use a blade designed for cutting metal to avoid damaging the tool.
Sheet aluminium can be cut without the need for a guillotine or tin-snips which tend to deform the metal. With the aid of a straight-edge and a sharp knife "score" BOTH sides of the aluminium sheet. This weakens the aluminium and creates a "fracture line".
Generally, all alkali metals can be easily cut with a knife.
Copper, Aluminium, and Iron are hard metals with iron being the hardest amongst the given options. They cannot be cut easily with a knife as they have stronger metallic bonds.
Sodium is silver white color metal with malleable and ductile property. It is the metal that can easily be cut with a knife. It is a good conductor of heat and electricity.
Tungsten carbide rings are made of the hardest metal on earth. This is what gives it its scratch resistance, but this durability also means these rings resist cutting tools.
Alkali metals (lithium, sodium, potassium) are so soft that they can be cut with a knife.
Chromium: The Hardest Metal on Earth
Chromium is the hardest metal known to man. While you may not have heard of chromium, more than likely you've heard of stainless steel. Chromium is the key ingredient in stainless steel, thus it is used in a variety of settings.
Generally, metals are hard as they retain their shape even if pressure is applied. But, sodium and potassium are two exceptional metals that are soft and can be cut even with a knife.
Avoid using your knife on surfaces made of glass, granite, marble, or ceramic. These materials are much harder than steel and will weaken your knife's edge. Even a quick slice on a ceramic dinner plate, a marble cheese board, or a granite countertop can dull your knife.
Lead can be cut with a knife and scratched with finger nail, as lead is quite soft.
Lithium, sodium and potassium are all soft metals that are easily cut with a scalpel or knife.
Tungsten, which is Swedish for "heavy stone," is the strongest metal in the world. It was identified as a new element in 1781. It is commonly used to make bullets and missiles, metal evaporation work, manufacturing of paints, creating electron and Television tubes, and making glass to metal seals.
Metals like Gold and Iron are hard and dense . They are malleable and ductile. They are very tough and it's nearly impossible to be cut with a knife. Proper machines and techniques are used to cut such metals.
Yeah, its true that we cannot cut goldand platinum because they are very hard by nature unlike sodium and lithium which can be cut by knife. They have high tensile strength.
Cutting Tools for Making Jewelry:
Tube cutting jigs are used in conjunction with a jewelers saw. They hold your tubing (or large-gauge wire) in place so you can neatly make straight cut after straight cut, exactly the same length.
Copper is an excellent material for knives because it is naturally resistant to corrosion. As a result, copper Damascus blades will stay sharp for longer. Copper Damascus knives are also an excellent choice as kitchen knives.
You can cut aluminum using a non-ferrous metal cutting blade and a chop saw (miter saw). Avoid using an abrasive disc to remove aluminum on a chop saw designed for cutting metal. Aluminum will jam abrasive cutting discs, causing them to overheat and shatter.