When it comes to determining the "strongest" steel for swords, it is important to consider that different steel alloys offer a combination of properties that contribute to overall blade performance. Factors such as hardness, toughness, and edge retention all play a role in determining a steel's suitability for sword-making. Here are a few steel types often considered strong for sword blades:

1. High-Carbon Steel: High-carbon steels, such as 1095, are known for their excellent hardness, edge retention, and ease of sharpening. They can be heat-treated to achieve a high level of hardness, making them strong and capable of holding a sharp edge. However, they may require proper care and maintenance to prevent rust.
2. Tool Steel: Tool steels, such as D2 or A2, are specifically designed to withstand demanding applications and offer excellent strength, toughness, and wear resistance. They are often chosen for heavy-duty or hard-use swords that require durability and resistance to chipping or deformation.
3. Powder Metallurgy Steels: Powder metallurgy steels, like S30V or M390, are made using advanced manufacturing techniques that result in fine-grained steel with exceptional strength, wear resistance, and edge retention. These steels are often used in high-end or specialized swords that require superior performance.
4. Laminated Steels: Laminated steels, such as those used in traditional Japanese swords (katana), combine a hard and brittle edge steel (hagane) with a softer and more flexible spine (mune). This construction provides a combination of strength, edge retention, and resilience.

It's worth noting that the performance of a sword blade is not solely determined by the steel type but also by factors such as heat treatment, blade geometry, design, and the skill of the swordsmith. A well-made sword blade considers the intended use, balance, and overall design to optimize its performance.

When selecting a sword, it's recommended to consult with experienced swordsmiths, reputable dealers, or knowledgeable experts who can provide guidance based on your specific requirements and preferences.