A. Demirer et al. / Materials and Design 28 (2007)   1467–1476 1475

Density variation for ABS

1.16

1.15

1.14

1.13

1.12

1.11

1.1

50 40 40 70 60 50

Injection Pressure (MPa)

Fig. 11.  Density variation of the injected parts vs. process temperature and injection pressure for ABS polymer when using both HRS and CRS.

Fig. 12.  Density variation of the injected parts vs. process temperature and injection pressure for PP polymer when using both HRS and CRS.

Table 5

Density variation of the injected parts vs. process temperature and injection pressure for base polymers when using both HRS and CRS

Base polymer Process temperature (°C) HRS CRS

Injection pressure (MPa) Density (g/cm3) Injection pressure (MPa) Density (g/cm3)

ABS 245 50 1.159 70 1.136

260 40 1.158 60 1.131

280 40 1.157 50 1.117

PP 170 80 0.9652 80 0.9337

120 0.9683 120 0.9636

200 40 0.9605 70 0.9290

100 0.9655 100 0.9258

260 30 0.9370 45 0.9330

tance between the outermost edge of the part and the gate is smaller due to the nozzle location, and the pressure and heat losses are also lower due to the eliminating sprue. Thus,  the  packing  pressure  and  the  melt temperature,

which are the most influential process parameters on the void generation as mentioned above, can be  controlled more easily and accurately, so higher sample weights are achievable [10].

1476 A. Demirer et al. / Materials and Design 28 (2007) 1467–1476

The weights of the parts produced in the experiments were measured after 30 days. Figs. 11 and 12 show the vari- ations in densities of the injected parts vs. injection pressure for the experimented temperatures. According to these fig- ures, the density of the injected parts is higher at low tem- peratures than that of high temperatures. The increasing effect of injection pressure on density is also noticeable from the figures. It was observed that the densities of the samples increased with the increasing injection pressure. Determined sample densities vs. process temperature and injection pressure are presented in Table  5. 对热流道系统注塑工艺英文文献和中文翻译(8):http://www.youerw.com/fanyi/lunwen_76041.html