diff --git a/qt/python/mantidqt/widgets/sliceviewer/model.py b/qt/python/mantidqt/widgets/sliceviewer/model.py
index 7d80504c215a..096723475099 100644
--- a/qt/python/mantidqt/widgets/sliceviewer/model.py
+++ b/qt/python/mantidqt/widgets/sliceviewer/model.py
@@ -38,6 +38,7 @@ class SliceViewerModel:
     def __init__(self, ws):
         # reference to the workspace requested to be viewed
         self._ws = ws
+        self._ws_name = ws.name()
         if isinstance(ws, MatrixWorkspace):
             if ws.getNumberHistograms() < 2:
                 raise ValueError("workspace must contain at least 2 spectrum")
@@ -53,10 +54,9 @@ def __init__(self, ws):
         else:
             raise ValueError("only works for MatrixWorkspace and MDWorkspace")
 
-        wsname = self.get_ws_name()
-        self._rebinned_name = wsname + '_svrebinned'
-        self._xcut_name, self._ycut_name = wsname + '_cut_x', wsname + '_cut_y'
-        self._roi_name = wsname + '_roi'
+        self._rebinned_name = self._ws_name + '_svrebinned'
+        self._xcut_name, self._ycut_name = self._ws_name + '_cut_x', self._ws_name + '_cut_y'
+        self._roi_name = self._ws_name + '_roi'
 
         ws_type = self.get_ws_type()
         if ws_type == WS_TYPE.MDE:
@@ -126,9 +126,12 @@ def can_support_dynamic_rebinning(self) -> bool:
         return ws_type == WS_TYPE.MDE or (ws_type == WS_TYPE.MDH and self._get_ws().hasOriginalWorkspace(
             0) and self._get_ws().getOriginalWorkspace(0).getNumDims() == self._get_ws().getNumDims())
 
+    def set_ws_name(self, new_name):
+        self._ws_name = new_name
+
     def get_ws_name(self) -> str:
         """Return the name of the workspace being viewed"""
-        return self._ws.name()
+        return self._ws_name
 
     def get_frame(self) -> SpecialCoordinateSystem:
         """Return the coordinate system of the workspace"""
@@ -139,7 +142,7 @@ def get_title(self, ws_name=None) -> str:
         of the model's workspace if none supplied.
         """
         if not ws_name:
-            ws_name = self.get_ws_name()
+            ws_name = self._ws_name
         return f'Sliceviewer - {ws_name}'
 
     def get_ws_MDE(self,
@@ -497,7 +500,7 @@ def export_pixel_cut_to_workspace_matrix(self, slicepoint, bin_params, pos: tupl
         return help_msg
 
     def workspace_equals(self, ws_name):
-        return str(self._get_ws()) == ws_name
+        return self._ws_name == ws_name
 
     # private api
     def _get_ws(self):
diff --git a/qt/python/mantidqt/widgets/sliceviewer/presenter.py b/qt/python/mantidqt/widgets/sliceviewer/presenter.py
index 4abee0abe6ec..11bacfa4d892 100644
--- a/qt/python/mantidqt/widgets/sliceviewer/presenter.py
+++ b/qt/python/mantidqt/widgets/sliceviewer/presenter.py
@@ -439,11 +439,12 @@ def refresh_view(self):
             ws.unlock()
 
     def rename_workspace(self, old_name, new_name):
-        if str(self.model._get_ws()) == old_name:
+        if self.model.get_ws_name() == old_name:
+            self.model.set_ws_name(new_name)
             self.view.emit_rename(self.model.get_title(new_name))
 
     def delete_workspace(self, ws_name):
-        if ws_name == str(self.model._ws):
+        if ws_name == self.model.get_ws_name():
             self.view.emit_close()
 
     def ADS_cleared(self):