板材送进夹钳装置设计(工作原理+任务书+说明书+CAD图纸+英文参考文献) 第4页
mechanisms of (KC5010) under wet condition). After gradual wear stage the curves look parallel to each other. This shows that flank wear occurs at the same rate under dry and wet cutting conditions. The previous figures show that flank wear curves went through three stages of wear: running in wear stage, gradual wear stage or steady state wear, and followed by rapid, fatal wear. Similar observations were documented by Chubb and Billingham [11], Haron [12]. The following terminologies are used:
Initial or running in wear stage: takes place due to the rapid breakdown of the edge, which is shown by the initial high wear rate in the graph of wear against time. Curves 1, 2, and 3 in Figure 3-6 this stage is decreased as the cutting speed increased
Gradual wear stage: the figures of the three types of cutting inserts, after the initial wear has taken place, indicating a steady gradual stage on the insert wear will form. However, it will increase with less dramatic pattern than the initial stage.
Rapid, fatal wear: the final stage of wear, which leads to a catastrophic failure of the cutting inserts. Rapid fatal wear revealed both flank and large crater formation that weakened the tool edge and under sustained resistance to the high cutting forces, caused it to fracture. Testing methods indicated rapid breakdown took place during cutting; causing severe damage to take place on the work-piece surface. Therefore, imagining that the catastrophic failure took place during the final cutting pass at the work piece surface, it is highly likely that the work piece has to be scrapped.
Table 3-6 Cutting speeds used in the test for the specific type of inserts
Cutting Insert Cutting Speed (m/min)
KC313 60 90 120 150 180
KC5010 210 260 310 360 410
KC732 210 260 310 360 410
 Cemented Carbide (KC313)  (wet & dry)  
Time (min)
Figure 3-5 Flank wear as a function of cutting time for KC313 (dry and wet).TiN-TiCN-TiN(KC732)
(wet & dry)
Figure 3-6 Flank wear as a function of cutting time for KC732 (dry and wet).
TiALN(KC5010) (wet & dry)0.0 o     t t
  0 5 10 15 20 25 30 35 40 45 50 55 60 65
Time (min)
Figure 3-7 Flank wear as a function of cutting time for KC5010 (dry and wet).

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