Recommended Hardness for LC200N (and thoughts on AEB-L and 1084)?

[David Mary]

I will be making my first batch in LC200N shortly, and will most likely have @JTknives Jarod heat treat them for me. I am not entirely sure what hardness to request for the various types of knives I will be getting, and all the charts I have ever seen comparing its toughness to other steels omit to mention a hardness value.

At this time, I have a enough experience with 1084 and AEB-L, enough to say that in AEB-L, I like my machetes and choppers at RC 61, and my EDC knives and kitchen cutlery at RC 63. In 1084, I like my choppers at RC 60, my EDC and kitchen cutlery at 62.

I tend to grind my blades fairly thin, with kitchen cutlery and EDC stuff often coming in under .008" BTE, and even my machetes come as low as .020" or thinner. Choppers destined for hard use are closer .030". At these hardness levels and grinds, the blades have so far seemed either tough enough to withstand the uses they were designed for, or in cases of blades I did not test through use, at least tough enough to pass the brass rod edge flex test.

I would like to hear the thoughts and rationale on the recommended hardness levels for these three steels from more experienced makers, in order to help me make a decision on LC200N, and it couldn't hurt to also get second opinions on AEB-L and 1084.

Thanks!

@Larrin tagged you in for your wealth of knowledge

 

[Zeunerite]

Found a spec sheet with tempering chart.
http://www.carrs-tool.co.uk/wp-content/uploads/2019/11/LC200N.pdf

Looks like 59rc is as high as it goes or 61rc with a high temper if you're willing to sacrifice corrosion resistance.

 

[David Mary]

Thanks a lot Z Zeunerite . I guess the next question becomes at what hardness does Spyderco run their LC200N, as it seems to achieve an optimal balance of properties.

 

[Willie71]

It tops out at about Rc60 regardless of low or high temper. It denitrides too much when trying to get it harder. A nitrogen atmosphere might allow it to get harder, but I haven’t set up the chamber yet. I now have nitrogen in my shop.

It is pretty tough at Rc60. No point in going lower.

 

[David Mary]

Thank you Willie71 And it is still rustproof for you at that hardness?

 

[DevinT]

Thank you Willie71 And it is still rustproof for you at that hardness?

The harder it is the more stainless it is.

Hoss

 

[Willie71]

Thank you Willie71 And it is still rustproof for you at that hardness?

It still uses low temper protocol. VERY corrosion resistant. Moreso than any other knife steel. If you need more wear resistance, use Vanax.