diff --git a/python/damask/_configmaterial.py b/python/damask/_configmaterial.py
index 4f3eba816..6de2283f4 100644
--- a/python/damask/_configmaterial.py
+++ b/python/damask/_configmaterial.py
@@ -226,13 +226,13 @@ class ConfigMaterial(Config):
         return dup
 
 
-    def material_add(self,constituents,**kwargs):
+    def material_add(self,constituents=None,**kwargs):
         """
         Add material entries.
 
         Parameters
         ----------
-        constituents : dict
+        constituents : dict, optional
             Entries for 'constituents' as key-value pair.
         **kwargs
             Key-value pairs.
@@ -263,13 +263,26 @@ class ConfigMaterial(Config):
             homogenization: SX
 
         """
-        c = [{'constituents':u} for u in ConfigMaterial._constituents(**constituents)]
+        length = -1
+        for v in kwargs.values():
+            if hasattr(v,'__len__') and not isinstance(v,str):
+                if length != -1 and len(v) != length:
+                    raise ValueError('Cannot add entries of different length')
+                else:
+                    length = len(v)
+        length = max(1,length)
+
+        c = [{} for _ in range(length)] if constituents is None else \
+            [{'constituents':u} for u in ConfigMaterial._constituents(**constituents)]
+        if len(c) == 1: c = [copy.deepcopy(c[0]) for _ in range(length)]
+
+        if length != 1 and length != len(c):
+            raise ValueError('Cannot add entries of different length')
+
         for k,v in kwargs.items():
             if hasattr(v,'__len__') and not isinstance(v,str):
-                if len(v) != len(c):
-                    raise ValueError('Cannot add entries of different length')
                 for i,vv in enumerate(v):
-                    c[i][k] = [w.item() for w in vv] if isinstance(vv,np.ndarray) else vv.item()
+                    c[i][k] = vv.item() if isinstance(vv,np.generic) else vv
             else:
                 for i in range(len(c)):
                     c[i][k] = v
@@ -293,7 +306,7 @@ class ConfigMaterial(Config):
                     if len(v) != N_material:
                         raise ValueError('Cannot add entries of different length')
                     for i,vv in enumerate(np.array(v)):
-                        m[i][0][k] = [w.item() for w in vv] if isinstance(vv,np.ndarray) else vv.item()
+                        m[i][0][k] = vv.item() if isinstance(vv,np.generic) else vv
                 else:
                     for i in range(N_material):
                         m[i][0][k] = v
diff --git a/python/tests/test_ConfigMaterial.py b/python/tests/test_ConfigMaterial.py
index 0f2b6a90c..25c05d711 100644
--- a/python/tests/test_ConfigMaterial.py
+++ b/python/tests/test_ConfigMaterial.py
@@ -62,6 +62,12 @@ class TestConfigMaterial:
         del material_config['material'][0]['homogenization']
         assert not material_config.is_complete
 
+    def test_incomplete_homogenization_N_constituents(self,reference_dir):
+        material_config = ConfigMaterial.load(reference_dir/'material.yaml')
+        for h in material_config['homogenization'].keys():
+            del material_config['homogenization'][h]['N_constituents']
+        assert not material_config.is_complete
+
     def test_incomplete_phase_lattice(self,reference_dir):
         material_config = ConfigMaterial.load(reference_dir/'material.yaml')
         del material_config['phase']['Aluminum']['lattice']
@@ -85,9 +91,36 @@ class TestConfigMaterial:
         assert len(c['material']) == N
         for i,m in enumerate(c['material']):
             c = m['constituents'][0]
-            assert m['c'] == 1 and c['b'] == 0 and c['a'] == [i,1]
+            assert m['c'] == 1 and c['b'] == 0 and (c['a'] == [i,1]).all()
 
-    def test__constituents(self):
+    def test_constituents(self):
         c = ConfigMaterial._constituents(c=1,v=[2,3])
         assert c[0][0]['c'] == c[1][0]['c']    == 1
         assert c[0][0]['v'] == c[1][0]['v'] -1 ==2
+
+    @pytest.mark.parametrize('constituents',[{'W':1,'X':[2,3]},{'Y':4},{'Z':[5,6]}])
+    @pytest.mark.parametrize('a',[[7.,8.],9.])
+    @pytest.mark.parametrize('b',['bd',['efg','hi']])
+    def test_material_add(self,tmp_path,constituents,a,b):
+        len_c = len(ConfigMaterial()._constituents(1,**constituents))
+        len_a = len(a) if isinstance(a,list) else 1
+        len_b = len(b) if isinstance(b,list) else 1
+        m = ConfigMaterial().material_add(constituents,a=a,b=b)
+        m.save()
+        assert len(m['material']) == np.max([len_a,len_b,len_c])
+
+    @pytest.mark.parametrize('constituents',[{'W':1,'X':np.array([2,3])},{'Y':4},{'Z':np.array([5,6])}])
+    @pytest.mark.parametrize('a',[np.array([7,8]),9])
+    def test_material_add_np(self,tmp_path,constituents,a):
+        len_c = len(ConfigMaterial()._constituents(1,**constituents))
+        len_a = len(a) if isinstance(a,np.ndarray) else 1
+        m = ConfigMaterial().material_add(constituents,ld=a)
+        m.save()
+        assert len(m['material']) == np.max([len_a,len_c])
+
+    @pytest.mark.parametrize('constituents',[{'X':np.array([2,3,4,5])},{'Y':4}])
+    @pytest.mark.parametrize('a',[np.array([1,2,3]),[4,5,6]])
+    @pytest.mark.parametrize('b',[np.array([6.,7.]),[8.,9.]])
+    def test_material_add_invalid(self,constituents,a,b):
+        with pytest.raises(ValueError):
+            ConfigMaterial().material_add(constituents,a=a,u=b)