Here are two messages from an engineering forum.
I find it to be an intriguing question and thought others might also.
My thoughts / guesses are at the end of this.
tom
Message 1
IronAgeGeorge (Computer) Nov 18, 2002
Hi, I hope I've come to the right place, I'm an archaeology researcher located in England with an engineering background and I've been asked to help a fellow researcher looking into possible reasons for failure of Bronze Age copper alloy artifacts such as axes.
It occurs to me this is a field in which we are in desperate need of some expert help.
One of the object types in question are small bronze wood cutting axes, some of these have failed by a fracture which runs in parallel with the cutting edge, 1-2cm back, either the entire cutting edge is lost or it "hangs off", with a large crack running at least 50% of the blade length.
Some of these axes also show signs of sometimes extreme mis-use and there is a train of thought which suggests these items may have been "ritually" broken.
However, I have a feeling that a great many of these objects hay have failed as a normal part of the product "life cycle". If I remember correctly, an axe, even when used completely normally will eventually fail due to small fractures joining up?
Ideally I'd like to find some failure analysis on similar objects, So something on failure of axes or hammers, and something on failure of copper alloys would be really good.
If anyone is interested I'd also like information on abnormal use failures, it occurs to me that in some cases what we are seeing is damage caused by continuing use after an initial failure. Or that the artifact was used "against the manufacturers instructions".
I hope someone can help, or at least point me in the right direction. Sorry I'm such a novice, I did three months of material science as part of my electronics based apprenticeship, that was a long time ago and the electronics swiftly moved on to computers.
Message 2
IronAgeGeorge (Computer) Nov 19, 2002
I have scanned in one diagram I have showing an axe head which is seen as possibly being ritually broken.
http://www.smartgroups.com/pictures...reID=10490010&Layout=D&Sort=Ordernum&Dir=desc
Sorry it's not much good.
I've emailed my collegue for better pictures.
The text to accompany the axe head goes as follows:
"An axe blade for instance, was probably still shafted when a massive blow landed just below the onset of the haft, tearing the exposed part of the blade downwards, all but breaking it in two. It is significant that, despite further blows shown by dents and cracks on the thin edge of the flanges, the axe stayed in one piece." Louis Nebelsick.
The author then goes on to say that together with the other damaged objects in the hoard this shows clear evidence of Ritual breaking.
tomwalz (Materials) Nov 19, 2002
A is the axe head?
It is about 15 cm ( 6 )long and about 4.5 (1.77 ) cm. across at the widest part?
Was there a haft (shaft)? That seems a bit small for a handle but it looks like a good size to be hand held. In addition I dont see attachments points for a handle but it does look like the ridges on the left and right sides would have been a big help in gripping. In that case I would think the palm of the hand would be on the left side and the fingers on the right side. If there were handle I would expect the long part you grip to be on the right side.
It looks to me as though it might have been gripped with the left hand.
Cast material. Inclusions in it. Guy is holding it and beating on something. Handle starts to give way but his grip serves to keep the two pieces marginally aligned so he can get another couple swings.
I think that it may have broken / ripped where it did because of the arc of the swing. Maybe the user was cutting something below his shoulder, perhaps kneeling and working on the ground. The axe head would have impacted on the fingers side of the head.
Are there tide marks on the separation. Tide marks here means curved lines, one after another much like the waves leave marks on the shore. If the metal ripped a bit each time a blow was struck then each blow would have created a separate tide mark.
I dont know about a ritual breaking but I think that was a valuable tool. If it was cast metal then it should be easy to recast it using an open mold. In any case wouldnt the metal alone be worth saving?
What are chances it was broken by someone from a less sophisticated group than the group that made it originally? They didnt know how to use it so it broke? Once it was broken they had no idea how to fix it or that it could be fixed.
A nice shot of both sides of the rip would really help especially if it shows grain structure.
Interesting question.
Thanks
Tom
I find it to be an intriguing question and thought others might also.
My thoughts / guesses are at the end of this.
tom
Message 1
IronAgeGeorge (Computer) Nov 18, 2002
Hi, I hope I've come to the right place, I'm an archaeology researcher located in England with an engineering background and I've been asked to help a fellow researcher looking into possible reasons for failure of Bronze Age copper alloy artifacts such as axes.
It occurs to me this is a field in which we are in desperate need of some expert help.
One of the object types in question are small bronze wood cutting axes, some of these have failed by a fracture which runs in parallel with the cutting edge, 1-2cm back, either the entire cutting edge is lost or it "hangs off", with a large crack running at least 50% of the blade length.
Some of these axes also show signs of sometimes extreme mis-use and there is a train of thought which suggests these items may have been "ritually" broken.
However, I have a feeling that a great many of these objects hay have failed as a normal part of the product "life cycle". If I remember correctly, an axe, even when used completely normally will eventually fail due to small fractures joining up?
Ideally I'd like to find some failure analysis on similar objects, So something on failure of axes or hammers, and something on failure of copper alloys would be really good.
If anyone is interested I'd also like information on abnormal use failures, it occurs to me that in some cases what we are seeing is damage caused by continuing use after an initial failure. Or that the artifact was used "against the manufacturers instructions".
I hope someone can help, or at least point me in the right direction. Sorry I'm such a novice, I did three months of material science as part of my electronics based apprenticeship, that was a long time ago and the electronics swiftly moved on to computers.
Message 2
IronAgeGeorge (Computer) Nov 19, 2002
I have scanned in one diagram I have showing an axe head which is seen as possibly being ritually broken.
http://www.smartgroups.com/pictures...reID=10490010&Layout=D&Sort=Ordernum&Dir=desc
Sorry it's not much good.
I've emailed my collegue for better pictures.
The text to accompany the axe head goes as follows:
"An axe blade for instance, was probably still shafted when a massive blow landed just below the onset of the haft, tearing the exposed part of the blade downwards, all but breaking it in two. It is significant that, despite further blows shown by dents and cracks on the thin edge of the flanges, the axe stayed in one piece." Louis Nebelsick.
The author then goes on to say that together with the other damaged objects in the hoard this shows clear evidence of Ritual breaking.
tomwalz (Materials) Nov 19, 2002
A is the axe head?
It is about 15 cm ( 6 )long and about 4.5 (1.77 ) cm. across at the widest part?
Was there a haft (shaft)? That seems a bit small for a handle but it looks like a good size to be hand held. In addition I dont see attachments points for a handle but it does look like the ridges on the left and right sides would have been a big help in gripping. In that case I would think the palm of the hand would be on the left side and the fingers on the right side. If there were handle I would expect the long part you grip to be on the right side.
It looks to me as though it might have been gripped with the left hand.
Cast material. Inclusions in it. Guy is holding it and beating on something. Handle starts to give way but his grip serves to keep the two pieces marginally aligned so he can get another couple swings.
I think that it may have broken / ripped where it did because of the arc of the swing. Maybe the user was cutting something below his shoulder, perhaps kneeling and working on the ground. The axe head would have impacted on the fingers side of the head.
Are there tide marks on the separation. Tide marks here means curved lines, one after another much like the waves leave marks on the shore. If the metal ripped a bit each time a blow was struck then each blow would have created a separate tide mark.
I dont know about a ritual breaking but I think that was a valuable tool. If it was cast metal then it should be easy to recast it using an open mold. In any case wouldnt the metal alone be worth saving?
What are chances it was broken by someone from a less sophisticated group than the group that made it originally? They didnt know how to use it so it broke? Once it was broken they had no idea how to fix it or that it could be fixed.
A nice shot of both sides of the rip would really help especially if it shows grain structure.
Interesting question.
Thanks
Tom
