先贴代码。
Subscript[Q, crit] = 4 1/6 (1 + 2 \[Zeta]) CC;
ParametricPlot[{{(x^2 + 3 x^4 - (QQ/(4 CC))^2 + 2 x^2 \[Zeta])/(
4 \[Pi] R x^3) /. R -> 1 /. CC -> 1 /. \[Zeta] -> 0 /.
QQ -> 0.3, (CC (-x^4 + 3 (QQ/(4 CC))^2 + x^2 (1 + 2 \[Zeta])))/(
R x) /. R -> 1 /. CC -> 1 /. \[Zeta] -> 0 /.
QQ -> 0.3}, {(x^2 + 3 x^4 - (QQ/(4 CC))^2 + 2 x^2 \[Zeta])/(
4 \[Pi] R x^3) /. R -> 1 /. QQ -> Subscript[Q, crit] /.
CC -> 1 /. \[Zeta] ->
0, (CC (-x^4 + 3 (QQ/(4 CC))^2 + x^2 (1 + 2 \[Zeta])))/(R x) /.
R -> 1 /. QQ -> Subscript[Q, crit] /. CC -> 1 /. \[Zeta] ->
0}, {(x^2 + 3 x^4 - (QQ/(4 CC))^2 + 2 x^2 \[Zeta])/(
4 \[Pi] R x^3) /. R -> 1 /. CC -> 1 /. \[Zeta] -> 0 /.
QQ -> 1, (CC (-x^4 + 3 (QQ/(4 CC))^2 + x^2 (1 + 2 \[Zeta])))/(
R x) /. R -> 1 /. CC -> 1 /. \[Zeta] -> 0 /.
QQ -> 1}, {(x^2 + 3 x^4 - (QQ/(4 CC))^2 + 2 x^2 \[Zeta])/(
4 \[Pi] R x^3) /. R -> 1 /. CC -> 1 /. \[Zeta] -> 0.075 /.
QQ -> 0.3, (CC (-x^4 + 3 (QQ/(4 CC))^2 + x^2 (1 + 2 \[Zeta])))/(
R x) /. R -> 1 /. CC -> 1 /. \[Zeta] -> 0.075 /.
QQ -> 0.3}, {(x^2 + 3 x^4 - (QQ/(4 CC))^2 + 2 x^2 \[Zeta])/(
4 \[Pi] R x^3) /. R -> 1 /. QQ -> Subscript[Q, crit] /.
CC -> 1 /. \[Zeta] ->
0.075, (CC (-x^4 + 3 (QQ/(4 CC))^2 + x^2 (1 + 2 \[Zeta])))/(
R x) /. R -> 1 /. QQ -> Subscript[Q, crit] /.
CC -> 1 /. \[Zeta] ->
0.075}, {(x^2 + 3 x^4 - (QQ/(4 CC))^2 + 2 x^2 \[Zeta])/(
4 \[Pi] R x^3) /. R -> 1 /. CC -> 1 /. \[Zeta] -> 0.075 /.
QQ -> 1, (CC (-x^4 + 3 (QQ/(4 CC))^2 + x^2 (1 + 2 \[Zeta])))/(
R x) /. R -> 1 /. CC -> 1 /. \[Zeta] -> 0.075 /.
QQ -> 1}, {(x^2 + 3 x^4 - (QQ/(4 CC))^2 + 2 x^2 \[Zeta])/(
4 \[Pi] R x^3) /. R -> 1 /. CC -> 1 /. \[Zeta] -> 0.95 /.
QQ -> 0.3, (CC (-x^4 + 3 (QQ/(4 CC))^2 + x^2 (1 + 2 \[Zeta])))/(
R x) /. R -> 1 /. CC -> 1 /. \[Zeta] -> 0.95 /.
QQ -> 0.3}, {(x^2 + 3 x^4 - (QQ/(4 CC))^2 + 2 x^2 \[Zeta])/(
4 \[Pi] R x^3) /. R -> 1 /. QQ -> Subscript[Q, crit] /.
CC -> 1 /. \[Zeta] ->
0.95, (CC (-x^4 + 3 (QQ/(4 CC))^2 + x^2 (1 + 2 \[Zeta])))/(
R x) /. R -> 1 /. QQ -> Subscript[Q, crit] /.
CC -> 1 /. \[Zeta] ->
0.95}, {(x^2 + 3 x^4 - (QQ/(4 CC))^2 + 2 x^2 \[Zeta])/(
4 \[Pi] R x^3) /. R -> 1 /. CC -> 1 /. \[Zeta] -> 0.95 /.
QQ -> 2, (CC (-x^4 + 3 (QQ/(4 CC))^2 + x^2 (1 + 2 \[Zeta])))/(
R x) /. R -> 1 /. CC -> 1 /. \[Zeta] -> 0.95 /.
QQ -> 2}, {(x^2 + 3 x^4 - (QQ/(4 CC))^2 + 2 x^2 \[Zeta])/(
4 \[Pi] R x^3) /. R -> 1 /. CC -> 1 /. \[Zeta] -> 1.95 /.
QQ -> 0.3, (CC (-x^4 + 3 (QQ/(4 CC))^2 + x^2 (1 + 2 \[Zeta])))/(
R x) /. R -> 1 /. CC -> 1 /. \[Zeta] -> 1.95 /.
QQ -> 0.3}, {(x^2 + 3 x^4 - (QQ/(4 CC))^2 + 2 x^2 \[Zeta])/(
4 \[Pi] R x^3) /. R -> 1 /. QQ -> Subscript[Q, crit] /.
CC -> 1 /. \[Zeta] ->
1.95, (CC (-x^4 + 3 (QQ/(4 CC))^2 + x^2 (1 + 2 \[Zeta])))/(
R x) /. R -> 1 /. QQ -> Subscript[Q, crit] /.
CC -> 1 /. \[Zeta] ->
1.95}, {(x^2 + 3 x^4 - (QQ/(4 CC))^2 + 2 x^2 \[Zeta])/(
4 \[Pi] R x^3) /. R -> 1 /. CC -> 1 /. \[Zeta] -> 1.95 /.
QQ -> 3.3, (CC (-x^4 + 3 (QQ/(4 CC))^2 + x^2 (1 + 2 \[Zeta])))/(
R x) /. R -> 1 /. CC -> 1 /. \[Zeta] -> 1.95 /.
QQ -> 3.3}}, {x, 0, 15}, PlotRange -> {{0, 1.5}, {-1, 8}},
AspectRatio -> 1,
PlotStyle -> {{Red, Dotted}, {Red, Dashed}, {Red,
DotDashed}, {Orange, Dotted}, {Orange, Dashed}, {Orange,
DotDashed}, {Green, Dotted}, {Green, Dashed}, {Green,
DotDashed}, {Purple, Dotted}, {Purple, Dashed}, {Purple,
DotDashed}}, Frame -> True, FrameLabel -> {"T", "F"},
LabelStyle -> Directive[Black, 10], ImageSize -> 300]
运行代码，画出图像以后，过一会儿就出现未响应，每次都是这样，有人知道是什么原因吗？怎么解决这个问题呢

真心请教大家，这个问题困我好久了

忘了说，这里补充一下。我用的是13.2的版本

我又试了试11.3和12的版本，11.3画不出来图像，12可以画这个而且不会未响应。但是13.2就会未响应，这个代码就是13.2写的

11.3版本你试试把绘图范围改成{x, 0.01, 15}再画画看。（我这边这会儿没有11.3，但是在版本7复现了类似的问题，目测是x==0处的奇点导致的问题。）
未响应问题我这边没法复现。（不过13.2版我也没装。）非要猜的话，感觉可能是笔记本动态交互出了什么问题。总之你先试试把动态交互关掉。（相应选项在顶部菜单的“计算”里面。）
此外，ParametricPlot的第一个参数里加个Evaluate能提一点速，当然你这个代码本身也不算慢，所以无所谓。
最后，你这代码根本没必要写得这么啰嗦……你看看Table和Flatten的帮助吧。