Description
Hitachi SLD Tool Steel San Mai 410 Stainless Steel Clad
San-Mai rolled by Sanwa Special Steel company.
Hitachi SLD steel is a premium high-speed tool steel that has gained popularity among knifemakers due to its excellent wear resistance, toughness, and edge retention. Similar to D2 tool steel, it is a semi-stainless steel with a high carbon and chromium content, which provides it with good corrosion resistance and excellent edge retention properties. However, unlike D2, it has a higher vanadium content, which improves its wear resistance, making it an ideal choice for high-end kitchen knives and other cutting tools that require superior edge retention and durability. Hitachi SLD steel can be heat treated to a high hardness level and is relatively easy to work with, making it a popular choice among knifemakers looking for a premium steel that offers excellent performance and ease of use.
Carbon – 1.60%
Chromium – 11.00%
Molybdenum - 0.90%
Vanadium - 0.25%
Nickel - 0.50%
Manganese– 0.60%
Copper - 0.25%
Silicon – 0.10%
Phosphorus - 0.03%
Sulfer - 0.03%
Iron – Balance
Toughness 3.5/10 – Adequate toughness for most cutting tasks but not suitable for large blades subject to a lot of shock and stress, or blades with very thin geometry or fine cutting edges. SLD works best in small to medium sized blades where it can take a sharp edge and hold it all day. It has better toughness than extremely high carbide tool steels like CPM 15V and ZDP-189, lower toughness than most carbon steels, and comparable toughness to many common stainless steels like 440C, 154CM, and N690.
Edge retention 5/10 – Much better edge retention than any carbon steel and better than most stainless steels; lower edge retention than high vanadium stainless and tool steels like CPM S35VN, M390, or CPM M4. SLD's large carbides give it a reputation for taking a toothy edge.
Corrosion resistance 4.5/10 – Moderate resistance to rust, better than most tool steels, slightly less than CPM 3V, falling short of stainless steel corrosion resistance but a huge upgrade over carbon steel. With little maintenance even a SLD folding knife can stay rust free after years of use and pocket carry.
Recommended heat treatment
- Wrap blade in foil.
- Austenitise – heat to 1,0240°C and hold for 10 minutes
- Quench in Aluminium plates
- Temper at 185-200°C for 2 hours, twice, depending on desired hardness
Approximate as-quenched hardness before tempering:
- 1,030°C to 1,070°C followed by cooling to room temperature 64HRC
Recommended working hardness 58-60HRC
A low and long temper is recommended after your normal temper ~100c for 2+ hours to releive any additional stress in the blade and reduce core delamination possibili
