unusual keris

[mariusgmioc]

Originally Posted by Jean

I cannot believe that an acid-treated iron blade (and looking solid) can float on water unless it is hollow?

A normally acid treted iron blade won't float but one that has been turned into sponge will most likely float, at least for a while, until the air pockets within its structure get filled with water.

[satsujinken]

Originally Posted by mariusgmioc

A normally acid treted iron blade won't float but one that has been turned into sponge will most likely float, at least for a while, until the air pockets within its structure get filled with water.

the funny thing is the blade is light but not that spongy. It is solid ... trust me it really felt like wood, well - until you put a magnet unto it

too bad we live so far apart ... I am dreaming of a gathering in a room with coffee and lots of blades :P



Donny

[David]

Originally Posted by satsujinken

too bad we live so far apart ... I am dreaming of a gathering in a room with coffee and lots of blades :P

I support that dream!

[mariusgmioc]

Originally Posted by satsujinken

the funny thing is the blade is light but not that spongy. It is solid ... trust me it really felt like wood, well - until you put a magnet unto it.

Donny

Hello Donny,

If the blade weren't spongy it wouldn't float. So even if it is not plainly visible with naked eye under sufficient magnification, I am sure the structure would appear spongy.

[satsujinken]

Originally Posted by mariusgmioc

Hello Donny,

If the blade weren't spongy it wouldn't float. So even if it is not plainly visible with naked eye under sufficient magnification, I am sure the structure would appear spongy.

I'll take your word for it, Marius
at least for now

I will study this intriguing piece further and post any updates here

Donny

[Pusaka]

It is quite strange that it should float on water even if it were spongy, and then why should it be spongy? Acid would waste the blade away unless the alloy was composed of two metals one which is dissolved by acid whilst the other resistant.

Wire wool scrubbing pads are as spongy as you can get yet they dont float on water.

[mariusgmioc]

Originally Posted by Pusaka

It is quite strange that it should float on water even if it were spongy, and then why should it be spongy? Acid would waste the blade away unless the alloy was composed of two metals one which is dissolved by acid whilst the other resistant.

Wire wool scrubbing pads are as spongy as you can get yet they dont float on water.

No, wire wool is not spongy. Spongy means there are many micro cavities inside. When you carefully put it on water, then some air might get trapped in these micro-cavities and make it float. And considering that these cavities are of microscopic dimmensions, it might even be difficult for the water to get in.

Normally kerises are made of diferent alloys of iron, some more, some less resistant to acid attack. Yet, it wouldn't be the different alloys that may cause this phenomenon, but the intrinsic structure of iron. Iron is formed by a matrix of microcristals of Ferrite and Cementite. Ferrite is a high iron phase, while Cementite being a low iron border material between metal and ceramic. What I suspect it happened with this Keris is that the Ferrite was dissolved by the acid and left the cementite matrix intact.... more or less.

[Pusaka]

Originally Posted by mariusgmioc

No, wire wool is not spongy. Spongy means there are many micro cavities inside. When you carefully put it on water, then some air might get trapped in these micro-cavities and make it float. And considering that these cavities are of microscopic dimmensions, it might even be difficult for the water to get in.

Normally kerises are made of diferent alloys of iron, some more, some less resistant to acid attack. Yet, it wouldn't be the different alloys that may cause this phenomenon, but the intrinsic structure of iron. Iron is formed by a matrix of microcristals of Ferrite and Cementite. Ferrite is a high iron phase, while Cementite being a low iron border material between metal and ceramic. What I suspect it happened with this Keris is that the Ferrite was dissolved by the acid and left the cementite matrix intact.... more or less.

Dirty Iron is what we call Iron with lots of non metallic components. The forging process drives them out forming sparks as you strike the Iron. The purer the Iron becomes the less sparks formed. No keris could be spongy after being through the forging process. Keris blades are made from different types of besi (traditionally 16) they are all Iron just coming from different sources. I have seen a heavily pitted blade but never seen a spongy blade.

[Pusaka]

Originally Posted by satsujinken

I'll take your word for it, Marius
at least for now

I will study this intriguing piece further and post any updates here

Donny

Have you tried to prick the blade with a needle to see how hard the material is?