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leomet

Practice your writing skill here.

Which one carbide does more harm to the properties of the steel,

No. 1 or No. 2 ?  Why?

[ 本帖最后由 leomet 于 2009-8-7 08:18 编辑 ]

njxwl

I think No 2

leomet

Why  is it?

hlqhlq

I think No.2 ,too.
Because No.2 carbide is bigger than No.1 carbide although their form are different.

mvp

图片不是太清楚，但是从伤害来说，尖锐的碳化物肯定要比园块状的伤害大些，但是这个量上不好说，毕竟很大的一块碳化物放在哪里都有害

tom2005

I think sharp shape is easily to extend, but if it is round, it is not extend and damage.and you?

leomet

In the process of fracture failure of a tool steel, it is all about crack initiation.
Carbide particles with  sharp tips are most likely to induce microcrack first.
According to Griffith law, the smaller the tip radius, the larger the stress induced in front of the carbide tip.
Microcracks will coalesce into macrocracks and lead to facture at last.
The term "a/r" is a key factor in the initiation  of a microcrack.

[ 本帖最后由 leomet 于 2009-8-8 08:51 编辑 ]

chen4yun

Learning things！Glad to see that！

qinning_2001

In this way,the No.2 carbide may be more harmful to the material.
I wonder when the max stress of a sharp tips  exceed the yield stress or the tensile stress of the material,the crack will initiate?

liangdeyu

both 1 and 2 are all harmfu to steel.