You can create custom material rating bar by defining drawable xml using material icon of your choice and then applying custom drawable to rating bar using progressDrawable attribute.
For infomration about customizing rating bar see http://www.zoftino.com/android-ratingbar-and-custom-ratingbar-example
Below drawable xml uses thumbs up icon for rating bar.
<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
<item android:id="@android:id/background">
<bitmap
android:src="@drawable/thumb_up"
android:tint="?attr/colorControlNormal" />
</item>
<item android:id="@android:id/secondaryProgress">
<bitmap
android:src="@drawable/thumb_up"
android:tint="?attr/colorControlActivated" />
</item>
<item android:id="@android:id/progress">
<bitmap
android:src="@drawable/thumb_up"
android:tint="?attr/colorControlActivated" />
</item>
</layer-list>