Update

app/Http/Controllers/MaterielController.php

@@ -50,7 +50,7 @@ class MaterielController extends Controller
                 'quarter',
                 'lowest_price',
                 'highest_price',
-                'unit',
+                // 'unit',
             ])
         );
         $materiel->created_by = $user->id;

app/Http/Requestes/MaterielStoreRequest.php

@@ -23,7 +23,6 @@ class MaterielStoreRequest extends FormRequest
             'type' => ['required', new Enum(MaterielType::class)],
             'lowest_price' => ['required', 'int'],
             'highest_price' => ['required', 'int', 'gte:lowest_price'],
-            'unit' => ['required', 'string'],
         ];
     }
 
@@ -36,7 +35,6 @@ class MaterielStoreRequest extends FormRequest
             'type' => '类型',
             'lowest_price' => '最低价',
             'highest_price' => '最高价',
-            'unit' => '单位',
         ];
     }
 }

app/Models/Materiel.php

@@ -11,6 +11,10 @@ class Materiel extends Model
 {
     use Filterable, HasFactory;
 
+    protected $attributes = [
+        'unit' => '吨',
+    ];
+
     protected $casts = [
         'type' => MaterielType::class,
     ];