Tikz Graph Position in Research Paper

Question

I am using a tikz environment for drawing result graphs. After running the code graph are drawn at the bottom of the research paper after Reference heading, but in latex code for graph is inserted in between the research paper.

So, how to position graph in between research paper at their appropriate location.

\begin{figure}\small
        \begin{minipage}[b]{.57\linewidth}
            \centering
            \begin{tikzpicture}
            \begin{axis}[
            xlabel={Migration Time (Seconds)},
            ylabel={Bandwidth Transfer Rate (Mbps)},
            xmin=0, xmax=50,
            ymin=0, ymax=550,
            xtick={0,10,20,30,40,50},
            tick={0,100,200,300,400,500,550},
            legend pos=north west,
            %ymajorgrids=true,
            grid style=dashed,
            ]
            \addplot+[
            color=blue,
            mark size=50pt,
            mark=solid,
            style={ultra thick},
            ]
            coordinates {
                (14.551,100)
                (0,100)(10,100)(20,100)(30,100)(40,100) (50,100)};
            \legend{Idle VM}
            %\addlegendentry{Downtime:232ms}
            %\addplot [variable=\t,samples=200,domain=0:360] ({0.950052*cos(t)},{0.945021*sin(t)});
            %\addlegendentry{Parametric analytic}
            %\legend{Downtime:233ms}
            %\draw[blue] (axis cs: 28,131) -- (axis cs: 28,131)node[anchor=east,rotate=90]{Some label};
            %\draw (axis cs:28,axis cs:131);

            %\addplot[solid, purple, latex-latex]
            %coordinates{(28,0) (28,131)};

            \addplot[color=purple,mark=triangle*,mark size=2,style={thick},mark options={solid}] coordinates {
                (14.551,0)
                (14.551,100)
            };
            \node at (axis cs:38,500) {Downtime: 144 ms};

            %title={Fig. 1.Live Migration Process with Bw=131Mbps},
            \end{axis}
            %title={Temperature dependence of CuSO$_4\cdot$5H$_2$O solubility},

            \end{tikzpicture}
            \subcaption{Live Migration Process with Bw= 100 Mbps}\label{fig:10a}
        \end{minipage}
        \begin{minipage}[b]{.57\linewidth}
            \centering
            \begin{tikzpicture}
            \begin{axis}[
            xlabel={Migration Time (Seconds)},
            ylabel={Bandwidth Transfer Rate (Mbps)},
            xmin=0, xmax=50,
            ymin=0, ymax=550,
            xtick={0,10,20,30,40,50},
            tick={0,100,200,300,400,500,550},
            legend pos=north west,
            %ymajorgrids=true,
            grid style=dashed,
            ]

            \addplot+[
            color=blue,
            mark size=50pt,
            mark=solid,
            style={ultra thick},
            ]
            coordinates {
                (11.124,200)
                (0,200)(10,200)(20,200)(30,200)(40,200) (50,200)};
            \legend{Idle VM}
            %\addlegendentry{Downtime:232ms}
            %\addplot [variable=\t,samples=200,domain=0:360] ({0.950052*cos(t)},{0.945021*sin(t)});
            %\addlegendentry{Parametric analytic}
            %\legend{Downtime:233ms}
            %\draw[blue] (axis cs: 28,131) -- (axis cs: 28,131)node[anchor=east,rotate=90]{Some label};
            %\draw (axis cs:28,axis cs:131);

            %\addplot[solid, purple, latex-latex]
            %coordinates{(28,0) (28,131)};

            \addplot[color=purple,mark=triangle*,mark size=2,style={thick},mark options={solid}] coordinates {
                (11.124,0)
                (11.124,200)
            };
            \node at (axis cs:38,500) {Downtime: 92 ms};

            %title={Fig. 1.Live Migration Process with Bw=131Mbps},
            \end{axis}
            %title={Temperature dependence of CuSO$_4\cdot$5H$_2$O solubility},
            \end{tikzpicture}