Question: what is the strongest metal

It depends what you mean by strongest and also by metal.

There are 4 different types of strength that are defined – strength when being pulled (stretched), known as tensile strength; strength when being compressed (squeezed), sometimes also known as hardness; resistance to permanent defomation, known as yield strength, elastic strength; and strength under impact (sharp shocks) also known as toughness. Strength of one sort is often accompanied by weakness in others.

If we take just the elemental metals, Tungsten is the metal with the highest tensile strength – the greatest resistance to stretching, but it’s brittle and heavy. It’s impact strength is low, it shatters. Titanium has good tensile strength and is very light, but is also soft – it lacks hardness. Chromium has excellent hardness but has lesser tensile strength.

In selecting a metal to use engineers need to consider not just stength but also weight and corrosion resistance (as well as mundane things like cost, availability and how easy it is to work with). Strength is no use if most of that strength is spent supporting the metal itself because it’s so heavy. Tungsten is very strong but also very heavy (dense). It’s rare to find any significant structure made of tungsten – it’s most often used in alloys to improve their strength. Titanium is less strong but also much lighter. Strength is only good if it remains good for as long as you need it be good. If a metal looses its strength with time through corrosion or fatigue then it may be less useful than a weaker metal that keeps its strength.

In most applications alloys, blends of different metals to get the best properties and avoid the worst. Steel is one such alloy and has a huge number of different blends offering a very wide range of strengths and other properties, part of the reason it’s such a common material.