You can put 2 Y axis - PrimaryY and SecondaryY. You can try using:

<igCA:XamChart Name="xamChart1">

<igCA:XamChart.Axes>

<igCA:Axis AxisType="PrimaryY" Name="Y1" />

<igCA:Axis AxisType="SecondaryY" Name="Y2" />

</igCA:XamChart.Axes>

<igCA:XamChart.Series>

<igCA:Series ChartType="Line" AxisY="Y1">

<igCA:Series.DataPoints>

<igCA:DataPoint Value="4" />

<igCA:DataPoint Value="20" />

<igCA:DataPoint Value="30" />

<igCA:DataPoint Value="15" />

</igCA:Series.DataPoints>

<igCA:Series ChartType="Line" AxisY="Y2">

<igCA:Series.DataPoints>

<igCA:DataPoint Value="40" />

<igCA:DataPoint Value="800" />

<igCA:DataPoint Value="120" />

<igCA:DataPoint Value="350" />

</igCA:Series.DataPoints>

</igCA:Series>

</igCA:XamChart.Series>

</igCA:XamChart>

a CTP is available, but currently only for Silverlight: http://blogs.infragistics.com/blogs/jason_beres/archive/2009/11/18/announcing-silverlight-pivot-grid-datachart-ctp.aspx

http://help.infragistics.com/Help/NetAdvantage/WPFDV/2010.3/CLR4.0/html/SL_DV_Developers_Guide_xamWebDataChart.html

http://help.infragistics.com/Help/NetAdvantage/WPFDV/2010.3/CLR4.0/html/xamDataChart_Axes_Multiple_Axes.html

1: http://help.infragistics.com/doc/WPF/2013.2/CLR4.0/?page=xamDataChart_xamDataChart.html

2: http://help.infragistics.com/doc/WPF/2013.2/CLR4.0/?page=xamDataChart_Multiple_Axes.html